Add object event namespaces for the event IDs

Each unique event ID will thus be composed by 1 byte for the namespace
and 1 byte for a namespace-specific ID. The namespace for domain event
needs to be 0 for compatibility reasons.

src/conf/domain_event.c

@@ -1912,11 +1912,17 @@ virObjectEventStateDispatchFunc(virConnectPtr conn,
                                 void *opaque)
 {
     virObjectEventStatePtr state = opaque;
+    virEventNamespaceID namespace = (event->eventID & 0xFF00) >> 8;
 
     /* Drop the lock whle dispatching, for sake of re-entrancy */
     virObjectEventStateUnlock(state);
-    virDomainEventDispatchDefaultFunc(conn, event,
-            VIR_DOMAIN_EVENT_CALLBACK(cb), cbopaque, NULL);
+    switch (namespace)
+    {
+        case VIR_EVENT_NAMESPACE_DOMAIN:
+            virDomainEventDispatchDefaultFunc(conn, event,
+                    VIR_DOMAIN_EVENT_CALLBACK(cb), cbopaque, NULL);
+            break;
+    }
     virObjectEventStateLock(state);
 }
 

src/conf/domain_event.h

@@ -28,6 +28,14 @@
 
 # include "domain_conf.h"
 
+
+/** Event IDs are computed in the following way:
+    virEventNamespaceID << 8 + vir*EventId
+  */
+typedef enum {
+    VIR_EVENT_NAMESPACE_DOMAIN = 0, /* 0 to keep value of virDomainEventId unchanged */
+} virEventNamespaceID;
+
 typedef struct _virObjectEventCallback virObjectEventCallback;
 typedef virObjectEventCallback *virObjectEventCallbackPtr;