PYBIND11_EMBEDDED_MODULE replaced by OPM_EMBEDDED_MODULE.

python.cpp: PythonInterp created within contr. brackets.

PYBIND11_EMBEDDED_MODULE commented out.

opm_python: added file Embed.hpp.

introduced macro OPM_EMBEDDED_MODULE.

added opm_embedded_module.

using opm_embedded_module.

opm_embedded_module: commented out PyInstance check.

added namespace Opm::embed.

Embed.hpp -> EmbedModule.hpp.

Python.cpp: added exception if PyIsinstance.

parserstate: python is a unique_ptr.

Parser.cpp: exception if no Opm::python obj.

opm/parser/eclipse/Python/Python.hpp

@@ -60,8 +60,12 @@ public:
 private:
     std::shared_ptr<PythonInterp> interp;
 };
+
+std::unique_ptr<Python> PythonInstance();
+
 }
 
 
+
 #endif
 

src/opm/parser/eclipse/Parser/Parser.cpp

@@ -356,7 +356,7 @@ class ParserState {
         std::string lastKeyWord;
 
         Deck deck;
-        Python python;
+        std::unique_ptr<Python> python;
         const ParseContext& parseContext;
         ErrorGuard& errors;
         bool unknown_keyword = false;
@@ -411,6 +411,7 @@ ParserState::ParserState(const std::vector<std::pair<std::string, std::string>>&
                          ErrorGuard& errors_arg) :
     code_keywords(code_keywords_arg),
     parseContext( __parseContext ),
+    python( PythonInstance() ),
     errors( errors_arg )
 {}
 
@@ -421,6 +422,7 @@ ParserState::ParserState( const std::vector<std::pair<std::string, std::string>>
     code_keywords(code_keywords_arg),
     rootPath( boost::filesystem::canonical( p ).parent_path() ),
     parseContext( context ),
+    python( PythonInstance() ),
     errors( errors_arg )
 {
     openRootFile( p );
@@ -840,8 +842,12 @@ bool parseState( ParserState& parserState, const Parser& parser ) {
             }
             try {
                 if (rawKeyword->getKeywordName() ==  Opm::RawConsts::pyinput) {
-                    std::string python_string = rawKeyword->getFirstRecord().getRecordString();
-                    parserState.python.exec(python_string, parser, parserState.deck);
+                    if (parserState.python) {
+                        std::string python_string = rawKeyword->getFirstRecord().getRecordString();
+                        parserState.python->exec(python_string, parser, parserState.deck);
+                    }
+                    else
+                        throw std::logic_error("Cannot yet embed Python while still running Python.");
                 }
                 else
                     parserState.deck.addKeyword( parserKeyword.parse( parserState.parseContext,

src/opm/parser/eclipse/Python/EmbedModule.hpp

@@ -0,0 +1,58 @@
+/*
+This Code is a copy paste of part of the contents of pybind11/embed.h
+It allows for slightly changing the python embedding without changing the pybind11 sourcecode.
+*/
+
+#ifndef OPM_EMBED_MODULE
+#define OPM_EMBED_MODULE
+
+#ifdef EMBEDDED_PYTHON
+#include <pybind11/embed.h>
+
+#define OPM_EMBEDDED_MODULE(name, variable)                              \
+    static void PYBIND11_CONCAT(pybind11_init_, name)(pybind11::module &);    \
+    static PyObject PYBIND11_CONCAT(*pybind11_init_wrapper_, name)() {        \
+        auto m = pybind11::module(PYBIND11_TOSTRING(name));                   \
+        try {                                                                 \
+            PYBIND11_CONCAT(pybind11_init_, name)(m);                         \
+            return m.ptr();                                                   \
+        } catch (pybind11::error_already_set &e) {                            \
+            PyErr_SetString(PyExc_ImportError, e.what());                     \
+            return nullptr;                                                   \
+        } catch (const std::exception &e) {                                   \
+            PyErr_SetString(PyExc_ImportError, e.what());                     \
+            return nullptr;                                                   \
+        }                                                                     \
+    }                                                                         \
+    PYBIND11_EMBEDDED_MODULE_IMPL(name)                                       \
+    Opm::embed::python_module name(PYBIND11_TOSTRING(name),           \
+                               PYBIND11_CONCAT(pybind11_init_impl_, name));   \
+    void PYBIND11_CONCAT(pybind11_init_, name)(pybind11::module &variable)
+
+namespace Opm {
+namespace embed {
+
+/// Python 2.7/3.x compatible version of `PyImport_AppendInittab` and error checks.
+struct python_module {
+#if PY_MAJOR_VERSION >= 3
+    using init_t = PyObject *(*)();
+#else
+    using init_t = void (*)();
+#endif
+    python_module(const char *name, init_t init) {
+
+        auto result = PyImport_AppendInittab(name, init);
+        if (result == -1)
+            pybind11::pybind11_fail("Insufficient memory to add a new module");
+    }
+};  
+
+}
+}
+
+
+
+
+#endif
+
+#endif

src/opm/parser/eclipse/Python/Python.cpp

@@ -23,12 +23,11 @@
 
 namespace Opm {
 
-Python::Python():
-    interp(std::make_shared<PythonInterp>())
+Python::Python() :
+    interp(std::make_shared<PythonInterp>())    
 {
 }
 
-
 bool Python::exec(const std::string& python_code) const {
     this->interp->exec(python_code);
     return true;
@@ -50,5 +49,12 @@ Python::operator bool() const {
         return false;
 }
 
+std::unique_ptr<Python> PythonInstance() {
+    if (Py_IsInitialized())
+        return NULL;
+    
+    return std::make_unique<Python>();
+}
+
 
 }

src/opm/parser/eclipse/Python/PythonInterp.cpp

@@ -27,11 +27,12 @@
 
 #include "python/cxx/export.hpp"
 #include "PythonInterp.hpp"
+#include "EmbedModule.hpp"
 
 namespace py = pybind11;
 namespace Opm {
 
-PYBIND11_EMBEDDED_MODULE(context, module) {
+OPM_EMBEDDED_MODULE(context, module) {
     python::common::export_all(module);
 }
 

src/opm/parser/eclipse/Python/PythonInterp.hpp

@@ -18,8 +18,8 @@
 */
 
 
-#ifndef EMBEDDED_PYTHON_INTERP
-#define EMBEDDED_PYTHON_INTERP
+#ifndef PYTHON_INTERP
+#define PYTHON_INTERP
 
 #include <string>
 #include <stdexcept>