gre: move to a plugin

Move GRE folder under vnet to the plugin folder, and modify some of path
of the #inlude<header> to the new path.

Add a plugin.c file to register a plugin.

JIRA: VPP-2044

Type: improvement
Change-Id: I7f64cecd97538a7492e56a41558dab58281a9fa5
Signed-off-by: Chuhao Tang <nicotang@cisco.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/src/plugins/gre/plugin.c b/src/plugins/gre/plugin.c
new file mode 100644
index 00000000000..b92ec0b6dcd
--- /dev/null
+++ b/src/plugins/gre/plugin.c
@@ -0,0 +1,26 @@
+/*
+ * plugin.c: gre
+ *
+ * Copyright (c) 2023 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vlib/vlib.h>
+#include <vnet/plugin/plugin.h>
+#include <vpp/app/version.h>
+
+// register a plugin
+VLIB_PLUGIN_REGISTER () = {
+  .version = VPP_BUILD_VER,
+  .description = "Generic Routing Encapsulation (GRE) plugin",
+};