Fixed memory leaks involving Settings class

Settings (being a singleton) will now free it's instance itself upon program termination.

src/storm.cpp

@@ -99,18 +99,15 @@ bool parseOptions(const int argc, const char* argv[]) {
 	} catch (storm::exceptions::InvalidSettingsException& e) {
 		std::cout << "Could not recover from settings error: " << e.what() << "." << std::endl;
 		std::cout << std::endl << storm::settings::help;
-		delete s;
 		return false;
 	}
 	
 	if (s->isSet("help")) {
 		std::cout << storm::settings::help;
-		delete s;
 		return false;
 	}
 	if (s->isSet("test-prctl")) {
 		storm::parser::PrctlParser parser(s->getString("test-prctl").c_str());
-		delete s;
 		return false;
 	}
 	
@@ -133,9 +130,7 @@ bool parseOptions(const int argc, const char* argv[]) {
  * Function to perform some cleanup.
  */
 void cleanUp() {
-	if (storm::settings::instance() != nullptr) {
-		delete storm::settings::instance();
-	}
+	// nothing here
 }
 
 void testCheckingDie(storm::models::Dtmc<double>& dtmc) {

src/utility/Settings.cpp

@@ -33,6 +33,8 @@ storm::settings::Settings* storm::settings::Settings::inst = nullptr;
 
 std::map< std::pair<std::string, std::string>, std::shared_ptr<bpo::options_description> > storm::settings::Settings::modules;
 
+storm::settings::Destroyer storm::settings::Settings::destroyer;
+
 /*!
  *	The constructor fills the option descriptions, parses the
  *	command line and the config file and puts the option values to

src/utility/Settings.h

@@ -27,6 +27,8 @@ namespace settings {
 	
 	namespace bpo = boost::program_options;
 	
+	class Destroyer;
+	
 	/*!
 	 *	@brief	Wrapper around boost::program_options to handle configuration options.
 	 *
@@ -43,8 +45,7 @@ namespace settings {
 	 *	option modules. An option module can be anything that implements the
 	 *	interface specified by registerModule().
 	 */
-	class Settings
-	{
+	class Settings {
 		public:
 		
 			/*!
@@ -123,13 +124,26 @@ namespace settings {
 			friend std::ostream& helpConfigfile(std::ostream& os);
 			friend Settings* instance();
 			friend Settings* newInstance(int const argc, char const * const argv[], char const * const filename, bool const sloppy = false);
+			friend Destroyer;
 
 		private:
 			/*!
-			 *	@brief	Constructor.
+			 *	@brief	Private constructor.
+			 *
+			 *	This constructor is private, as noone should be able to create
+			 *	an instance manually, one should always use the
+			 *	newInstance() method.
 			 */
 			Settings(int const argc, char const * const argv[], char const * const filename, bool const sloppy);
 			
+			/*!
+			 *	@brief	Private destructor.
+			 *
+			 *	This destructor should be private, as noone should be able to destroy a singleton.
+			 *	The object is automatically destroyed when the program terminates by the destroyer.
+			 */
+			~Settings() {}
+			
 			/*!
 			 *	@brief	Initialize options_description object.
 			 */
@@ -174,6 +188,33 @@ namespace settings {
 			 *	@brief	actual instance of this class.
 			 */
  			static Settings* inst;
+ 			
+ 			/*!
+ 			 *	@brief	Destroyer object.
+ 			 */
+ 			static Destroyer destroyer;
+	};
+
+	/*!
+	 *	@brief	Destroyer class for singleton object of Settings.
+	 *
+	 *	The sole purpose of this class is to clean up the singleton object
+	 *	instance of Settings. The Settings class has a static member of this
+	 *	Destroyer type that gets cleaned up when the program terminates. In
+	 *	it's destructor, this object will remove the Settings instance.
+	 */
+	class Destroyer {
+		public:
+			/*!
+			 *	@brief	Destructor.
+			 *
+			 *	Free Settings::inst.
+			 */
+			~Destroyer() {
+				if (Settings::inst != nullptr) {
+					delete Settings::inst;
+				}
+			}
 	};
 	
 	/*!

test/storm-tests.cpp

@@ -42,13 +42,11 @@ bool parseOptions(int const argc, char const * const argv[]) {
     } catch (storm::exceptions::InvalidSettingsException& e) {
         std::cout << "Could not recover from settings error: " << e.what() << "." << std::endl;
         std::cout << std::endl << storm::settings::help;
-        delete s;
         return false;
     }
     
     if (s->isSet("help")) {
         std::cout << storm::settings::help;
-        delete s;
         return false;
     }