From be5318fdb0fbb7a447e68fad6787e2b6e221a20d Mon Sep 17 00:00:00 2001
From: Patrick Shriwise <pshriwise@gmail.com>
Date: Wed, 8 Jul 2020 21:16:36 -0500
Subject: [PATCH] Reorganizing some of the DAGMC-related code and using shared
 pointers instead.

---
 include/openmc/cell.h    | 17 ++++++++++++++++-
 include/openmc/dagmc.h   |  4 ++--
 include/openmc/surface.h |  2 +-
 src/cell.cpp             | 16 ++++++++++++++++
 src/dagmc.cpp            | 17 +++++++----------
 src/finalize.cpp         |  3 ---
 6 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/include/openmc/cell.h b/include/openmc/cell.h
index c7ba0ab13..282f00fff 100644
--- a/include/openmc/cell.h
+++ b/include/openmc/cell.h
@@ -75,6 +75,20 @@ public:
   unique_ptr<UniversePartitioner> partitioner_;
 };
 
+#ifdef DAGMC
+
+class DAGUniverse : public Universe {
+
+public:
+  explicit DAGUniverse(std::string filename);
+
+
+  // Data Members
+  std::shared_ptr<moab::DagMC> dag_instance_; //! DAGMC Instance for this universe
+};
+
+#endif
+
 //==============================================================================
 //==============================================================================
 
@@ -271,7 +285,7 @@ public:
 
   void to_hdf5(hid_t group_id) const;
 
-  moab::DagMC* dagmc_ptr_; //!< Pointer to DagMC instance
+  std::shared_ptr<moab::DagMC> dagmc_ptr_; //!< Pointer to DagMC instance
   int32_t dag_index_;      //!< DagMC index of cell
 };
 #endif
@@ -343,6 +357,7 @@ struct CellInstanceHash {
 void read_cells(pugi::xml_node node);
 
 #ifdef DAGMC
+void read_dagmc_universes(pugi::xml_node node);
 int32_t next_cell(DAGCell* cur_cell, DAGSurface* surf_xed);
 #endif
 
diff --git a/include/openmc/dagmc.h b/include/openmc/dagmc.h
index 9f409d873..81aa163dc 100644
--- a/include/openmc/dagmc.h
+++ b/include/openmc/dagmc.h
@@ -15,7 +15,7 @@ extern "C" const bool DAGMC_ENABLED;
 namespace openmc {
 
 namespace model {
-  extern moab::DagMC* DAG;
+  extern std::shared_ptr<moab::DagMC> DAG;
 }
 
 //==============================================================================
@@ -23,7 +23,7 @@ namespace model {
 //==============================================================================
 
 void load_dagmc_geometry();
-void free_memory_dagmc();
+void create_dagmc_universe(const std::string& filename);
 void read_geometry_dagmc();
 bool read_uwuw_materials(pugi::xml_document& doc);
 bool get_uwuw_materials_xml(std::string& s);
diff --git a/include/openmc/surface.h b/include/openmc/surface.h
index 5a8a88aa4..b729514b9 100644
--- a/include/openmc/surface.h
+++ b/include/openmc/surface.h
@@ -168,7 +168,7 @@ public:
 
   void to_hdf5(hid_t group_id) const;
 
-  moab::DagMC* dagmc_ptr_; //!< Pointer to DagMC instance
+  std::shared_ptr<moab::DagMC> dagmc_ptr_; //!< Pointer to DagMC instance
   int32_t dag_index_;      //!< DagMC index of surface
 };
 #endif
diff --git a/src/cell.cpp b/src/cell.cpp
index 6b88a6780..733b70f05 100644
--- a/src/cell.cpp
+++ b/src/cell.cpp
@@ -1013,6 +1013,11 @@ void read_cells(pugi::xml_node node)
     }
   }
 
+#ifdef DAGMC
+  // read any DAGMC universes
+  read_dagmc_universes(node);
+#endif
+
   // Populate the Universe vector and map.
   for (int i = 0; i < model::cells.size(); i++) {
     int32_t uid = model::cells[i]->universe_;
@@ -1034,6 +1039,17 @@ void read_cells(pugi::xml_node node)
   }
 }
 
+void read_dagmc_universes(pugi::xml_node node) {
+
+  // determine the max cell id
+  int32_t next_cell_id = 0;
+  for (const auto& c : model::cells) {
+    if (c->id_ > next_cell_id) next_cell_id = c->id_;
+  }
+  next_cell_id++;
+
+}
+
 //==============================================================================
 // C-API functions
 //==============================================================================
diff --git a/src/dagmc.cpp b/src/dagmc.cpp
index 0c2768834..5b8a61f7e 100644
--- a/src/dagmc.cpp
+++ b/src/dagmc.cpp
@@ -41,7 +41,7 @@ const std::string DAGMC_FILENAME = "dagmc.h5m";
 
 namespace model {
 
-moab::DagMC* DAG;
+std::shared_ptr<moab::DagMC> DAG;
 
 } // namespace model
 
@@ -151,14 +151,17 @@ void legacy_assign_material(std::string mat_string, DAGCell* c)
 
 void load_dagmc_geometry()
 {
+  create_dagmc_universe(dagmc_file());
+}
+
+void create_dagmc_universe(const std::string& filename) {
   if (!model::DAG) {
-    model::DAG = new moab::DagMC();
+    model::DAG = std::make_shared<moab::DagMC>();
   }
 
   // --- Materials ---
 
   // create uwuw instance
-  auto filename = dagmc_file();
   UWUW uwuw(filename.c_str());
 
   // check for uwuw material definitions
@@ -180,7 +183,7 @@ void load_dagmc_geometry()
   MB_CHK_ERR_CONT(rval);
 
   // parse model metadata
-  dagmcMetaData DMD(model::DAG, false, false);
+  dagmcMetaData DMD(model::DAG.get(), false, false);
   DMD.load_property_data();
 
   vector<std::string> keywords {"temp"};
@@ -346,11 +349,5 @@ void read_geometry_dagmc()
   model::root_universe = find_root_universe();
 }
 
-void free_memory_dagmc()
-{
-  delete model::DAG;
-}
-
-
 }
 #endif
diff --git a/src/finalize.cpp b/src/finalize.cpp
index 22dc67183..54a8d681d 100644
--- a/src/finalize.cpp
+++ b/src/finalize.cpp
@@ -51,9 +51,6 @@ void free_memory()
   if (settings::event_based) {
     free_event_queues();
   }
-#ifdef DAGMC
-  free_memory_dagmc();
-#endif
 }
 
 }