rpc: virnetserverclient: Implement client connection transport retrieval

Although we document 6 types of transport that we support, internally we can
only differentiate between TCP, TLS, and UNIX transports only, since both SSH
and libssh2 transports, due to using netcat, behave in the exactly the same
way as a UNIX socket.
Signed-off-by: NErik Skultety <eskultet@redhat.com>

src/libvirt_remote.syms

@@ -125,6 +125,7 @@ virNetServerClientGetIdentity;
 virNetServerClientGetPrivateData;
 virNetServerClientGetReadonly;
 virNetServerClientGetSELinuxContext;
+virNetServerClientGetTransport;
 virNetServerClientGetUNIXIdentity;
 virNetServerClientImmediateClose;
 virNetServerClientInit;

src/rpc/virnetserverclient.c

@@ -1568,3 +1568,25 @@ virNetServerClientStartKeepAlive(virNetServerClientPtr client)
     virObjectUnlock(client);
     return ret;
 }
+
+int
+virNetServerClientGetTransport(virNetServerClientPtr client)
+{
+    int ret = -1;
+
+    virObjectLock(client);
+
+    if (client->sock && virNetSocketIsLocal(client->sock))
+        ret = VIR_CLIENT_TRANS_UNIX;
+    else
+        ret = VIR_CLIENT_TRANS_TCP;
+
+#ifdef WITH_GNUTLS
+    if (client->tls)
+        ret = VIR_CLIENT_TRANS_TLS;
+#endif
+
+    virObjectUnlock(client);
+
+    return ret;
+}

src/rpc/virnetserverclient.h

@@ -145,5 +145,6 @@ int virNetServerClientSendMessage(virNetServerClientPtr client,
 
 bool virNetServerClientNeedAuth(virNetServerClientPtr client);
 
+int virNetServerClientGetTransport(virNetServerClientPtr client);
 
 #endif /* __VIR_NET_SERVER_CLIENT_H__ */