Merge another big set of changes from team/russell/events

This commit merges in the rest of the code needed to support distributed device
state.  There are two main parts to this commit.

Core changes:
 - The device state handling in the core has been updated to understand device
   state across a cluster of Asterisk servers.  Every time the state of a device
   changes, it looks at all of the device states on each node, and determines the
   aggregate device state.  That resulting device state is what is provided to
   modules in Asterisk that take actions based on the state of a device.

New module, res_ais:
 - A module has been written to facilitate the communication of events between
   nodes in a cluster of Asterisk servers.  This module uses the SAForum AIS
   (Service Availability Forum Application Interface Specification) CLM and EVT
   services (Cluster Management and Event) to handle this task.  This module
   currently supports sharing Voicemail MWI (Message Waiting Indication) and
   device state events between servers.  It has been tested with openais, though
   other implementations of the spec do exist.

For more information on testing distributed device state, see the following doc:
  - doc/distributed_devstate.txt


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@121559 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 48 insertions, 0 deletions

diff --git a/res/ais/ais.h b/res/ais/ais.h
new file mode 100644
index 000000000..2c4c18a87
--- /dev/null
+++ b/res/ais/ais.h
@@ -0,0 +1,48 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2007, Digium, Inc.
+ *
+ * Russell Bryant <russell@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! 
+ * \file
+ * \author Russell Bryant <russell@digium.com>
+ *
+ * \brief Usage of the SAForum AIS (Application Interface Specification)
+ *
+ * \arg http://www.openais.org/
+ */
+
+#ifndef AST_AIS_H
+#define AST_AIS_H
+
+#include <openais/saAis.h>
+#include <openais/saClm.h>
+#include <openais/saEvt.h>
+
+extern SaVersionT ais_version;
+
+extern SaClmHandleT  clm_handle;
+extern SaEvtHandleT  evt_handle;
+
+int ast_ais_clm_load_module(void);
+int ast_ais_clm_unload_module(void);
+
+int ast_ais_evt_load_module(void);
+int ast_ais_evt_unload_module(void);
+
+const char *ais_err2str(SaAisErrorT error);
+
+#endif /* AST_AIS_H */