guard boost::python::object

Author: basisunus

src/Core/Python/PythonDatatypeConverter.cc

@@ -77,7 +77,7 @@ struct PythonObjectVisitor : boost::static_visitor<py::object>
 struct ValueVisitor : boost::static_visitor<Variable::Value>
 {
 private:
-  const py::object& object_;
+  py::object object_;
 public:
   explicit ValueVisitor(const py::object& object) : object_(object) {}
 
@@ -132,10 +132,12 @@ struct ValueVisitor : boost::static_visitor<Variable::Value>
       const auto firstVal = v[0];
       const py::extract<py::list> e(object_);
       auto pyList = e();
+      auto gil = PyGILState_Ensure();
       Variable::List newList(py::len(pyList));
       for (auto i = 0; i < py::len(pyList); ++i)
         newList[i] = Variable(firstVal.name(),
                               boost::apply_visitor(ValueVisitor(pyList[i]), firstVal.value()));
+      PyGILState_Release(gil);
       return newList;
     }
     else
@@ -626,7 +628,10 @@ Variable SCIRun::Core::Python::convertPythonObjectToVariable(const py::object& o
 Variable SCIRun::Core::Python::convertPythonObjectToVariableWithTypeInference(
     const py::object& object, const Variable& var)
 {
-  return Variable(var.name(), boost::apply_visitor(ValueVisitor(object), var.value()));
+  auto gil = PyGILState_Ensure();
+  Variable result(var.name(), boost::apply_visitor(ValueVisitor(object), var.value()));
+  PyGILState_Release(gil);
+  return result;
 }
 
 py::object SCIRun::Core::Python::convertVariableToPythonObject(const Variable& var)

src/Core/Python/PythonDatatypeConverter.h

@@ -105,13 +105,23 @@ namespace SCIRun
       class SCISHARE DatatypePythonExtractor
       {
       public:
-        virtual ~DatatypePythonExtractor() {}
+        virtual ~DatatypePythonExtractor()
+        {
+            PyGILState_STATE gil = PyGILState_Ensure();
+            try
+            {
+              object_ = boost::python::object();  // release
+            }
+            catch (...)
+            {}
+            PyGILState_Release(gil);
+        }
         explicit DatatypePythonExtractor(const boost::python::object& object) : object_(object) {}
         virtual bool check() const = 0;
         virtual Datatypes::DatatypeHandle operator()() const = 0;
         virtual std::string label() const = 0;
       protected:
-        const boost::python::object& object_;
+        boost::python::object object_;
       };
 
       class SCISHARE DenseMatrixExtractor : public DatatypePythonExtractor

src/Core/Python/PythonInterpreter.cc

@@ -232,7 +232,7 @@ PythonInterpreter::PythonInterpreter() : private_(new PythonInterpreterPrivate)
 PythonInterpreter::~PythonInterpreter()
 {
   // NOTE: Boost.Python requires that we don't call Py_Finalize
-  // Py_Finalize();
+  Py_Finalize();
 }
 
 // #define PRINT_PY_INIT_DEBUG(n) std::cout << "ev " << (n) << std::endl;

src/Dataflow/Engine/Controller/PythonImpl.cc

@@ -70,6 +70,15 @@ namespace
   class PyDatatypeString : public PyDatatype
   {
   public:
+    ~PyDatatypeString()
+    {
+      if (Py_IsInitialized())
+      {
+        PyGILState_STATE gil = PyGILState_Ensure();
+        str_ = py::object();  // release under GIL
+        PyGILState_Release(gil);
+      }
+    }
     explicit PyDatatypeString(StringHandle underlying) : underlying_(underlying), str_(convertStringToPython(underlying))
     {
     }