vconn: Add extern "C" { ... } for C++ header support.

diff --git a/lib/vconn.h b/lib/vconn.h
index 1426c1d..a9b0c7e 100644 (file)
--- a/lib/vconn.h
+++ b/lib/vconn.h
@@ -24,6 +24,10 @@
 
 #include "flow.h"
 
+#ifdef  __cplusplus
+extern "C" {
+#endif
+
 struct ofpbuf;
 struct ofp_action_header;
 struct ofp_header;
@@ -136,4 +140,8 @@ ofp_mkerr(uint16_t type, uint16_t code)
     return (type << 16) | code;
 }
 
+#ifdef  __cplusplus
+}
+#endif
+
 #endif /* vconn.h */