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, 35 insertions, 0 deletions

diff --git a/src/plugins/gre/CMakeLists.txt b/src/plugins/gre/CMakeLists.txt
new file mode 100644
index 00000000000..60fe540b968
--- /dev/null
+++ b/src/plugins/gre/CMakeLists.txt
@@ -0,0 +1,35 @@
+# 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.
+
+add_vpp_plugin(gre
+  SOURCES
+  gre.c
+  node.c
+  gre_api.c
+  interface.c
+  pg.c
+  plugin.c
+
+  MULTIARCH_SOURCES
+  node.c
+  gre.c
+
+  INSTALL_HEADERS
+  gre.h
+  error.def
+
+  API_FILES
+  gre.api
+
+)
+