make singleton thread safe

src/PyWrap.cc

@@ -7,9 +7,11 @@
 
 namespace pywrap {
     PyWrap* PyWrap::wrapper = nullptr;
+    std::mutex PyWrap::mutex;
 
     PyWrap* PyWrap::GetInstance()
     {
+        std::lock_guard<std::mutex> lock(mutex);
         if (wrapper == nullptr) {
             std::cout << "Creando instancia" << std::endl;
             wrapper = new PyWrap();
@@ -35,15 +37,15 @@ namespace pywrap {
             return;
         }
         std::cout << "No estaba en el mapa" << std::endl;
-        module = PyImport_ImportModule(moduleName.c_str());
+        PyObject* module = PyImport_ImportModule(moduleName.c_str());
         if (PyErr_Occurred()) {
             errorAbort("Could't import module " + moduleName);
         }
-        classObject = PyObject_GetAttrString(module, className.c_str());
+        PyObject* classObject = PyObject_GetAttrString(module, className.c_str());
         if (PyErr_Occurred()) {
             errorAbort("Couldn't find class " + className);
         }
-        instance = PyObject_CallObject(classObject, NULL);
+        PyObject* instance = PyObject_CallObject(classObject, NULL);
         if (PyErr_Occurred()) {
             errorAbort("Couldn't create instance of class " + className);
         }
@@ -89,7 +91,7 @@ namespace pywrap {
             errorAbort("Module " + moduleName + " and class " + className + " not found");
         }
         std::cout << "Clase encontrada" << std::endl;
-        instance = std::get<2>(item->second);
+        PyObject* instance = std::get<2>(item->second);
         PyObject* result;
         if (!(result = PyObject_CallMethod(instance, method.c_str(), NULL)))
             errorAbort("Couldn't call method " + method);

src/PyWrap.h

@@ -4,6 +4,7 @@
 #include <string>
 #include <map>
 #include <tuple>
+#include <mutex>
 
 namespace pywrap {
     /*
@@ -24,10 +25,8 @@ namespace pywrap {
         void errorAbort(const std::string& message);
         PyStatus initPython();
         static PyWrap* wrapper;
+        static std::mutex mutex;
         std::map<std::pair<std::string, std::string>, std::tuple<PyObject*, PyObject*, PyObject*>> moduleClassMap;
-        PyObject* module;
-        PyObject* classObject;
-        PyObject* instance;
     };
 } /* namespace python */
 #endif /* PYWRAP_H */