From baf31fdeeed3226cb54474c1d42f543d4d0929bf Mon Sep 17 00:00:00 2001
From: Darragh O'Reilly <dara2002-openstack@yahoo.com>
Date: Tue, 10 Sep 2013 09:06:28 +0000
Subject: [PATCH] Ensure pid file is removed when metadata ns daemon receives
 SIGTERM

These files from the metadata namespace proxy are not being removed
because delete_pid() is registered with atexit. This means it only runs
when a process exits normally and won't run when a process receives a
signal.

This patch registers a signal handler for SIGTERM that calls exit()
to make the process exit normally so delete_pid() gets called.

Fixes bug: 1223250

Change-Id: I6309802e2109359560ccc084559ec8e4d310cce2
---
 neutron/agent/linux/daemon.py           |  5 +++++
 neutron/tests/unit/test_linux_daemon.py | 21 +++++++++++++++------
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/neutron/agent/linux/daemon.py b/neutron/agent/linux/daemon.py
index 2825679a3a..3df12d580e 100644
--- a/neutron/agent/linux/daemon.py
+++ b/neutron/agent/linux/daemon.py
@@ -19,6 +19,7 @@
 import atexit
 import fcntl
 import os
+import signal
 import sys
 
 from neutron.agent.linux import utils
@@ -123,11 +124,15 @@ class Daemon(object):
 
         # write pidfile
         atexit.register(self.delete_pid)
+        signal.signal(signal.SIGTERM, self.handle_sigterm)
         self.pidfile.write(os.getpid())
 
     def delete_pid(self):
         os.remove(str(self.pidfile))
 
+    def handle_sigterm(self, signum, frame):
+        sys.exit(0)
+
     def start(self):
         """Start the daemon."""
 
diff --git a/neutron/tests/unit/test_linux_daemon.py b/neutron/tests/unit/test_linux_daemon.py
index 2fc27a4aab..c4cf3223ce 100644
--- a/neutron/tests/unit/test_linux_daemon.py
+++ b/neutron/tests/unit/test_linux_daemon.py
@@ -160,13 +160,16 @@ class TestDaemon(base.BaseTestCase):
         d = daemon.Daemon('pidfile')
         with mock.patch.object(d, '_fork') as fork:
             with mock.patch.object(daemon, 'atexit') as atexit:
-                with mock.patch.object(daemon, 'sys') as sys:
-                    sys.stdin.fileno.return_value = 0
-                    sys.stdout.fileno.return_value = 1
-                    sys.stderr.fileno.return_value = 2
-                    d.daemonize()
-                    atexit.register.assert_called_once_with(d.delete_pid)
+                with mock.patch.object(daemon, 'signal') as signal:
+                    signal.SIGTERM = 15
+                    with mock.patch.object(daemon, 'sys') as sys:
+                        sys.stdin.fileno.return_value = 0
+                        sys.stdout.fileno.return_value = 1
+                        sys.stderr.fileno.return_value = 2
+                        d.daemonize()
 
+                    signal.signal.assert_called_once_with(15, d.handle_sigterm)
+                atexit.register.assert_called_once_with(d.delete_pid)
             fork.assert_has_calls([mock.call(), mock.call()])
 
         self.os.assert_has_calls([
@@ -185,6 +188,12 @@ class TestDaemon(base.BaseTestCase):
         d.delete_pid()
         self.os.remove.assert_called_once_with('pidfile')
 
+    def test_handle_sigterm(self):
+        d = daemon.Daemon('pidfile')
+        with mock.patch.object(daemon, 'sys') as sys:
+            d.handle_sigterm(15, 1234)
+            sys.exit.assert_called_once_with(0)
+
     def test_start(self):
         self.pidfile.return_value.is_running.return_value = False
         d = daemon.Daemon('pidfile')