Use C bindings in MPI example

examples/extended/parallel/MPI/README.md

@@ -27,9 +27,9 @@ http://www.open-mpi.org/
 MPI support:
 ------------
 G4mpi has been tested with the following MPI flavors:
- *   OpenMPI 1.8.1
- *   MPICH 3.2
- *   Intel MPI 5.0.1
+ *   OpenMPI 5.0.2 and 4.1.4
+ *   ~~MPICH 3.2~~
+ *   ~~Intel MPI 5.0.1~~
 
 ### CMake
 

examples/extended/parallel/MPI/source/CMakeLists.txt

@@ -10,7 +10,7 @@ project(${_projname})
 
 cmake_minimum_required(VERSION 3.16...3.27)
 find_package(MPI REQUIRED)
-find_package(Geant4 10.2.0 REQUIRED)
+find_package(Geant4 REQUIRED)
 include(${Geant4_USE_FILE})
 
 #------------------------------------------------------------------------------

examples/extended/parallel/MPI/source/include/G4MPImanager.hh

@@ -34,6 +34,7 @@
 
 #include <fstream>
 #include <pthread.h>
+#include <vector>
 
 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \
   TypeName(const TypeName&);               \
@@ -123,11 +124,14 @@ class G4MPImanager
     // misc
     void ShowHelp() const;
 
-    const MPI::Intracomm* GetComm() const { return &COMM_G4COMMAND_; }
+    const MPI_Comm* GetComm() const { return &COMM_G4COMMAND_; }
     const MPI_Comm* GetProcessingComm() const { return &processing_comm_; }
     const MPI_Comm* GetCollectingComm() const { return &collecting_comm_; }
     const MPI_Comm* GetAllComm() const { return &all_comm_; }
 
+    std::vector<G4String> ReturnArguments() { return _options; }
+
+
   private:
     DISALLOW_COPY_AND_ASSIGN(G4MPImanager);
 
@@ -153,11 +157,12 @@ class G4MPImanager
     G4bool is_slave_;
     G4bool is_extra_worker_;
     G4int rank_;
+    G4int provided_;
     G4int size_;  // processing comm size
     G4int world_size_;  // world comm size
 
     // MPI communicator (when no extra ranks)
-    MPI::Intracomm COMM_G4COMMAND_;
+    MPI_Comm COMM_G4COMMAND_;
     // MPI communicator (processing ranks - if ntuple merging)
     MPI_Comm processing_comm_;
     // MPI communicator (collecting ranks - if ntuple merging)
@@ -188,6 +193,8 @@ class G4MPImanager
     // parallel parameters
     G4double master_weight_;
     G4int nof_extra_workers_;
+
+    std::vector<G4String> _options;
 };
 
 // ====================================================================

examples/extended/parallel/MPI/source/include/G4MPIscorerMerger.hh

@@ -2,24 +2,24 @@
 // ********************************************************************
 // * License and Disclaimer                                           *
 // *                                                                  *
-// * The  Geant4 software  is  copyright of the Copyright Holders  of *
-// * the Geant4 Collaboration.  It is provided  under  the terms  and *
-// * conditions of the Geant4 Software License,  included in the file *
-// * LICENSE and available at  http://cern.ch/geant4/license .  These *
+// * The Geant4 software is copyright of the Copyright Holders of *
+// * the Geant4 Collaboration. It is provided under the terms and *
+// * conditions of the Geant4 Software License, included in the file *
+// * LICENSE and available at http://cern.ch/geant4/license. These *
 // * include a list of copyright holders.                             *
 // *                                                                  *
 // * Neither the authors of this software system, nor their employing *
-// * institutes,nor the agencies providing financial support for this *
-// * work  make  any representation or  warranty, express or implied, *
-// * regarding  this  software system or assume any liability for its *
-// * use.  Please see the license in the file  LICENSE  and URL above *
+// * institutes, nor the agencies providing financial support for this *
+// * work make any representation or warranty, express or implied, *
+// * regarding this software system or assume any liability for its *
+// * use. Please see the license in the file LICENSE and URL above *
 // * for the full disclaimer and the limitation of liability.         *
 // *                                                                  *
-// * This  code  implementation is the result of  the  scientific and *
+// * This code implementation is the result of the scientific and *
 // * technical work of the GEANT4 collaboration.                      *
-// * By using,  copying,  modifying or  distributing the software (or *
-// * any work based  on the software)  you  agree  to acknowledge its *
-// * use  in  resulting  scientific  publications,  and indicate your *
+// * By using, copying, modifying or distributing the software (or *
+// * any work based on the software) you agree to acknowledge its *
+// * use in resulting scientific publications, and indicate your *
 // * acceptance of all terms of the Geant4 Software license.          *
 // ********************************************************************
 //
@@ -103,8 +103,9 @@ class G4MPIscorerMerger
     G4ScoringManager* scoringManager;
     unsigned int commSize;
     unsigned int destinationRank;
-    MPI::Intracomm comm;
+    MPI_Comm comm;  // Changed from MPI::Intracomm to MPI_Comm
     G4int verbose;
+    void G4mpi_barrier(MPI_Comm* comm) {MPI_Barrier(*comm);};
 };
 
 #endif  // G4MPISCORERMERGER_HH

examples/extended/parallel/MPI/source/include/G4VUserMPIrunMerger.hh

@@ -50,16 +50,16 @@ class G4VUserMPIrunMerger
     virtual void Pack() = 0;
     virtual G4Run* UnPack() = 0;
 
-    void InputUserData(/*const*/ void* input_data, const MPI::Datatype& dt, int count)
+    void InputUserData(/*const*/ void* input_data, const MPI_Datatype& dt, int count)
     {
       input_userdata.push_back(const_registered_data{input_data, dt, count});
     }
-    void OutputUserData(void* input_data, const MPI::Datatype& dt, int count)
+    void OutputUserData(void* input_data, const MPI_Datatype& dt, int count)
     {
       output_userdata.push_back(registered_data{input_data, dt, count});
     }
 
-    // void GetUserData(void* output_data,const MPI::Datatype& dt, int count);
+    // void GetUserData(void* output_data,const MPI_Datatype& dt, int count);
 
     void SetupOutputBuffer(char* buff, G4int size, G4int position)
     {
@@ -91,7 +91,7 @@ class G4VUserMPIrunMerger
     unsigned int destinationRank;
     G4Run* run;
     unsigned int commSize;
-    MPI::Intracomm COMM_G4COMMAND_;
+    MPI_Comm COMM_G4COMMAND_;
     G4int verbose;
     long bytesSent;
 
@@ -103,7 +103,7 @@ class G4VUserMPIrunMerger
         // const_registered_data(const_registered_data&&) = default;
         // const_registered_data& operator=(const_registered_data&&) = default;
         /*const*/ void* p_data;
-        /*const*/ MPI::Datatype dt;
+        /*const*/ MPI_Datatype dt;
         /*const*/ int count;
     };
     std::vector<const_registered_data> input_userdata;
@@ -114,7 +114,7 @@ class G4VUserMPIrunMerger
         registered_data(const registered_data&) = default;
         registered_data& operator=(const registered_data&) = default;
         void* p_data;
-        /*const*/ MPI::Datatype dt;
+        /*const*/ MPI_Datatype dt;
         /*const*/ int count;
     };
     std::vector<registered_data> output_userdata;

examples/extended/parallel/MPI/source/src/G4MPIhistoMerger.cc

@@ -52,8 +52,9 @@ void G4MPIhistoMerger::Merge()
     G4cout << "Starting merging of histograms" << G4endl;
   }
 
-  const MPI::Intracomm* parentComm = G4MPImanager::GetManager()->GetComm();
-  MPI::Intracomm comm = parentComm->Dup();
+  const MPI_Comm* parentComm = G4MPImanager::GetManager()->GetComm();
+  MPI_Comm comm;// = parentComm->Dup();
+  MPI_Comm_dup(*parentComm, &comm);
 
   G4bool verbose = (verboseLevel > 1);
   G4int tag = G4MPImanager::kTAG_HISTO;
@@ -68,5 +69,5 @@ void G4MPIhistoMerger::Merge()
   if (verboseLevel > 0) {
     G4cout << "End merging of histograms" << G4endl;
   }
-  comm.Free();
+  MPI_Comm_free(&comm);
 }