From 19731869d365caaf7f37db73949d97c018e06054 Mon Sep 17 00:00:00 2001
From: Matthias Hochsteger <mhochsteger@cerbsim.com>
Date: Mon, 13 May 2024 18:10:36 +0200
Subject: [PATCH] Utility header to convert to native mpi handles

---
 libsrc/core/CMakeLists.txt    |  2 +-
 libsrc/core/ng_mpi_native.hpp | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 libsrc/core/ng_mpi_native.hpp

diff --git a/libsrc/core/CMakeLists.txt b/libsrc/core/CMakeLists.txt
index 71cbf0bc..eca94b8c 100644
--- a/libsrc/core/CMakeLists.txt
+++ b/libsrc/core/CMakeLists.txt
@@ -93,7 +93,7 @@ install(FILES ngcore.hpp archive.hpp type_traits.hpp version.hpp ngcore_api.hpp
   xbool.hpp signal.hpp bitarray.hpp table.hpp hashtable.hpp ranges.hpp ngstream.hpp
   simd.hpp simd_avx.hpp simd_avx512.hpp simd_generic.hpp simd_sse.hpp simd_arm64.hpp
   register_archive.hpp autodiff.hpp autodiffdiff.hpp
-  ng_mpi.hpp ng_mpi_generated_declarations.hpp
+  ng_mpi.hpp ng_mpi_generated_declarations.hpp ng_mpi_native.hpp
   DESTINATION ${NG_INSTALL_DIR_INCLUDE}/core COMPONENT netgen_devel)
 
 if(ENABLE_CPP_CORE_GUIDELINES_CHECK)
diff --git a/libsrc/core/ng_mpi_native.hpp b/libsrc/core/ng_mpi_native.hpp
new file mode 100644
index 00000000..6c8f40ce
--- /dev/null
+++ b/libsrc/core/ng_mpi_native.hpp
@@ -0,0 +1,21 @@
+#ifndef NG_MPI_NATIVE_HPP
+#define NG_MPI_NATIVE_HPP
+
+#include <mpi.h>
+
+#include "mpi_wrapper.hpp"
+#include "ng_mpi.hpp"
+
+namespace ngcore {
+
+MPI_Comm NG_MPI_Native(NG_MPI_Comm comm) {
+  return reinterpret_cast<MPI_Comm>(comm.value);
+}
+
+MPI_Comm NG_MPI_Native(NgMPI_Comm comm) {
+  return reinterpret_cast<MPI_Comm>(static_cast<NG_MPI_Comm>(comm).value);
+}
+
+}  // namespace ngcore
+
+#endif  // NG_MPI_NATIVE_HPP