session: add support for application namespacing

Applications are now provided the option to select the namespace they
are to be attached to and the scope of their attachement. Application
namespaces are meant to:
1) constrain the scope of communication through the network by
association with source interfaces and/or fib tables that provide the
source ips to be used and limit the scope of routing
2) provide a namespace local scope to session layer communication, as
opposed to the global scope provided by 1). That is, sessions can be
established without assistance from transport and network layers.
Albeit, zero/local-host ip addresses must still be provided in session
establishment messages due to existing application idiosyncrasies. This
mode of communication uses shared-memory fifos (cut-through sessions)
exclusively.

If applications request no namespace, they are assigned to the default
one, which at its turn uses the default fib. Applications can request
access to both local and global scopes for a namespace. If no scope is
specified, session layer defaults to the global one.

When a sw_if_index is provided for a namespace, zero-ip (INADDR_ANY)
binds are converted to binds to the requested interface.

Change-Id: Ia0f660bbf7eec7f89673f75b4821fc7c3d58e3d1
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/session/session_debug.h b/src/vnet/session/session_debug.h
index eb11f1a..d9b7103 100644
--- a/src/vnet/session/session_debug.h
+++ b/src/vnet/session/session_debug.h
@@ -31,11 +31,13 @@
 #undef _
 } session_evt_dbg_e;
 
-#define SESSION_DBG (0)
+#define SESSION_DEBUG (0 && TRANSPORT_DEBUG)
 #define SESSION_DEQ_NODE_EVTS (0)
 #define SESSION_EVT_POLL_DBG (1)
 
-#if TRANSPORT_DEBUG && SESSION_DBG
+#if SESSION_DEBUG
+
+#define SESSION_DBG(_fmt, _args...) clib_warning (_fmt, ##_args)
 
 #define DEC_SESSION_ETD(_s, _e, _size)					\
   struct								\
@@ -78,7 +80,7 @@
   do { _body; } while (0);						\
 }
 
-#if SESSION_DEQ_NODE_EVTS
+#if SESSION_DEQ_NODE_EVTS && SESSION_DEBUG > 1
 #define SESSION_EVT_DEQ_NODE_HANDLER(_node_evt)				\
 {									\
   ELOG_TYPE_DECLARE (_e) =						\
@@ -96,9 +98,9 @@
 }
 #else
 #define SESSION_EVT_DEQ_NODE_HANDLER(_node_evt)
-#endif
+#endif /* SESSION_DEQ_NODE_EVTS */
 
-#if SESSION_DBG && SESSION_EVT_POLL_DBG
+#if SESSION_EVT_POLL_DBG && SESSION_DEBUG > 1
 #define SESSION_EVT_POLL_GAP(_smm, _my_thread_index)			\
 {									\
   ELOG_TYPE_DECLARE (_e) =						\
@@ -122,7 +124,7 @@
 #else
 #define SESSION_EVT_POLL_GAP(_smm, _my_thread_index)
 #define SESSION_EVT_POLL_GAP_TRACK_HANDLER(_smm, _my_thread_index)
-#endif
+#endif /* SESSION_EVT_POLL_DBG */
 
 #define CONCAT_HELPER(_a, _b) _a##_b
 #define CC(_a, _b) CONCAT_HELPER(_a, _b)
@@ -130,7 +132,8 @@
 
 #else
 #define SESSION_EVT_DBG(_evt, _args...)
-#endif
+#define SESSION_DBG(_fmt, _args...)
+#endif /* SESSION_DEBUG */
 
 #endif /* SRC_VNET_SESSION_SESSION_DEBUG_H_ */
 /*