QMP: Introduce VNC_INITIALIZED event

It's emitted when a VNC client session is activated by QEMU,
client's information such as port, IP and auth ID (if the
session is authenticated) are provided.

Event example:

{ "event": "VNC_INITIALIZED",
    "timestamp": {"seconds": 1263475302, "microseconds": 150772},
    "data": {
        "server": { "auth": "sasl", "family": "ipv4",
                    "service": "5901", "host": "0.0.0.0"},
        "client": { "family": "ipv4", "service": "46089",
                    "host": "127.0.0.1", "sasl_username": "lcapitulino" } } }
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

QMP/qmp-events.txt

@@ -37,3 +37,9 @@ except that authentication ID is not provided.
 
 Description: Issued when the conection is closed.
 Data: 'server' and 'client' keys with the same keys as 'query-vnc'.
+
+6 VNC_INITIALIZED
+-----------------
+
+Description: Issued when the VNC session is made active.
+Data: 'server' and 'client' keys with the same keys as 'query-vnc'.

monitor.c

@@ -360,6 +360,9 @@ void monitor_protocol_event(MonitorEvent event, QObject *data)
         case QEVENT_VNC_CONNECTED:
             event_name = "VNC_CONNECTED";
             break;
+        case QEVENT_VNC_INITIALIZED:
+            event_name = "VNC_INITIALIZED";
+            break;
         case QEVENT_VNC_DISCONNECTED:
             event_name = "VNC_DISCONNECTED";
             break;

monitor.h

@@ -21,6 +21,7 @@ typedef enum MonitorEvent {
     QEVENT_POWERDOWN,
     QEVENT_STOP,
     QEVENT_VNC_CONNECTED,
+    QEVENT_VNC_INITIALIZED,
     QEVENT_VNC_DISCONNECTED,
     QEVENT_MAX,
 } MonitorEvent;

vnc.c

@@ -2112,6 +2112,7 @@ static int protocol_client_init(VncState *vs, uint8_t *data, size_t len)
     vnc_flush(vs);
 
     vnc_client_cache_auth(vs);
+    vnc_qmp_event(vs, QEVENT_VNC_INITIALIZED);
 
     vnc_read_when(vs, protocol_client_msg, 1);