network: add virNetworkPortRef API

Normal practice is to provide a Ref API for all objects, but this was
forgotten for the virNetworkPortPtr object.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

include/libvirt/libvirt-network.h

@@ -455,4 +455,7 @@ virNetworkListAllPorts(virNetworkPtr network,
 int
 virNetworkPortFree(virNetworkPortPtr port);
 
+int
+virNetworkPortRef(virNetworkPortPtr port);
+
 #endif /* LIBVIRT_NETWORK_H */

src/libvirt-network.c

@@ -1690,3 +1690,35 @@ virNetworkPortFree(virNetworkPortPtr port)
     virObjectUnref(port);
     return 0;
 }
+
+
+/**
+ * virNetworkPortRef:
+ * @port: a network port object
+ *
+ * Increment the reference count on the network port. For each
+ * additional call to this method, there shall be a corresponding
+ * call to virNetworkPortFree to release the reference count, once
+ * the caller no longer needs the reference to this object.
+ *
+ * This method is typically useful for applications where multiple
+ * threads are using a network port, and it is required that the
+ * port remain resident until all threads have finished using
+ * it. ie, each new thread using a network port would increment
+ * the reference count.
+ *
+ * Returns 0 in case of success, -1 in case of failure.
+ */
+int
+virNetworkPortRef(virNetworkPortPtr port)
+{
+    VIR_DEBUG("port=%p refs=%d", port,
+              port ? port->parent.u.s.refs : 0);
+
+    virResetLastError();
+
+    virCheckNetworkPortReturn(port, -1);
+
+    virObjectRef(port);
+    return 0;
+}

src/libvirt_public.syms

@@ -831,6 +831,7 @@ LIBVIRT_5.5.0 {
         virNetworkPortGetUUIDString;
         virNetworkPortDelete;
         virNetworkPortFree;
+        virNetworkPortRef;
         virNetworkPortSetParameters;
 } LIBVIRT_5.2.0;