From a1a033f1b73b29cc0961ab062303d82c66908e8f Mon Sep 17 00:00:00 2001
From: Adam G Nelson <nelsonag@umich.edu>
Date: Sun, 17 Jun 2018 10:58:28 -0400
Subject: [PATCH] including write_message access from the C side

---
 src/error.F90          |  9 +++++++++
 src/error.h            | 21 ++++++++++++++++++++-
 src/mgxs_interface.cpp |  3 +--
 src/mgxs_interface.h   |  1 +
 4 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/src/error.F90 b/src/error.F90
index d041051d29..82b142b51e 100644
--- a/src/error.F90
+++ b/src/error.F90
@@ -265,4 +265,13 @@ contains
 
   end subroutine write_message
 
+  subroutine write_message_from_c(message, message_len, level) bind(C)
+    integer(C_INT),         intent(in), value :: message_len
+    character(kind=C_CHAR), intent(in)        :: message(message_len)
+    integer(C_INT),         intent(in), value :: level
+    character(message_len+1)                  :: message_out
+    write(message_out, *) message
+    call write_message(message_out, level)
+  end subroutine write_message_from_c
+
 end module error
diff --git a/src/error.h b/src/error.h
index 45d8bcdede..356dfd8010 100644
--- a/src/error.h
+++ b/src/error.h
@@ -11,7 +11,8 @@ namespace openmc {
 
 extern "C" void fatal_error_from_c(const char* message, int message_len);
 extern "C" void warning_from_c(const char* message, int message_len);
-
+extern "C" void write_message_from_c(const char* message, int message_len,
+                                     int level);
 
 inline
 void fatal_error(const char *message)
@@ -43,5 +44,23 @@ void warning(const std::stringstream& message)
   warning(message.str());
 }
 
+inline
+void write_message(const char* message, int level)
+{
+  write_message_from_c(message, strlen(message), level);
+}
+
+inline
+void write_message(const std::string& message, int level)
+{
+  write_message_from_c(message.c_str(), message.length(), level);
+}
+
+inline
+void write_message(const std::stringstream& message, int level)
+{
+  write_message(message.str(), level);
+}
+
 } // namespace openmc
 #endif // ERROR_H
diff --git a/src/mgxs_interface.cpp b/src/mgxs_interface.cpp
index 29202e49d5..45234f454d 100644
--- a/src/mgxs_interface.cpp
+++ b/src/mgxs_interface.cpp
@@ -19,8 +19,7 @@ add_mgxs_c(hid_t file_id, char* name, const int energy_groups,
   double_1dvec temperature;
   temperature.assign(temps, temps + n_temps);
 
-  // TODO: C++ replacement for write_message
-  // write_message("Loading " + std::string(names[i]) + " data...", 6);
+  write_message("Loading " + std::string(name) + " data...", 6);
 
   // Check to make sure cross section set exists in the library
   hid_t xs_grp;
diff --git a/src/mgxs_interface.h b/src/mgxs_interface.h
index 09993e9811..785f72b32f 100644
--- a/src/mgxs_interface.h
+++ b/src/mgxs_interface.h
@@ -4,6 +4,7 @@
 #ifndef MGXS_INTERFACE_H
 #define MGXS_INTERFACE_H
 
+#include "error.h"
 #include "mgxs.h"