SDL: Fix leaks related to graphics modes

supportedGraphicsModes() now returns to OSystem_SDL a pointer to a deep copy of
surfacesdl's internal graphics mode array. Therefore each can free its
own copy without interfering with the other's.

backends/graphics/surfacesdl/surfacesdl-graphics.cpp

@@ -77,6 +77,8 @@ const OSystem::GraphicsMode s_supportedStretchModes[] = {
 };
 #endif
 
+static void initGraphicsModes();
+
 DECLARE_TRANSLATION_ADDITIONAL_CONTEXT("Normal (no scaling)", "lowres")
 
 AspectRatio::AspectRatio(int w, int h) {
@@ -170,6 +172,9 @@ SurfaceSdlGraphicsManager::SurfaceSdlGraphicsManager(SdlEventSource *sdlEventSou
 #if SDL_VERSION_ATLEAST(2, 0, 0)
 	_videoMode.stretchMode = STRETCH_FIT;
 #endif
+
+	if (!s_supportedGraphicsModes)
+		initGraphicsModes();
 }
 
 SurfaceSdlGraphicsManager::~SurfaceSdlGraphicsManager() {
@@ -186,6 +191,16 @@ SurfaceSdlGraphicsManager::~SurfaceSdlGraphicsManager() {
 	free(_currentPalette);
 	free(_cursorPalette);
 	delete[] _mouseData;
+
+	for (uint i = 0; i < s_supportedGraphicsModes->size() - 1; ++i) {
+		OSystem::GraphicsMode &gm = (*s_supportedGraphicsModes)[i];
+		free(const_cast<char *>(gm.name));
+		free(const_cast<char *>(gm.description));
+	}
+	delete s_supportedGraphicsModes;
+	delete s_supportedGraphicsModesData;
+	s_supportedGraphicsModes = NULL;
+	s_supportedGraphicsModesData = NULL;
 }
 
 bool SurfaceSdlGraphicsManager::hasFeature(OSystem::Feature f) const {
@@ -259,12 +274,8 @@ void static initGraphicsModes () {
 		for (uint j = 0; j < factors.size(); ++j) {
 			Common::String n1 = Common::String::format("%s%dx", name, factors[j]);
 			Common::String n2 = Common::String::format("%s%dx", prettyName, factors[j]);
-			char *s1 = new char[n1.size()+1];
-			char *s2 = new char[n2.size()+1];
-			strcpy(s1, n1.c_str());
-			strcpy(s2, n2.c_str());
-			gm.name = s1;
-			gm.description = s2;
+			gm.name = strdup(n1.c_str());
+			gm.description = strdup(n2.c_str());
 			gm.id = s_supportedGraphicsModes->size();
 			s_supportedGraphicsModes->push_back(gm);
 			gmd.scaleFactor = factors[j];
@@ -280,7 +291,20 @@ void static initGraphicsModes () {
 const OSystem::GraphicsMode *SurfaceSdlGraphicsManager::supportedGraphicsModes() {
 	if (!s_supportedGraphicsModes)
 		initGraphicsModes();
-	return &(*s_supportedGraphicsModes)[0];
+
+	int size = s_supportedGraphicsModes->size();
+	OSystem::GraphicsMode *modes = new OSystem::GraphicsMode[size];
+	memcpy(modes, &(*s_supportedGraphicsModes)[0], size * sizeof(OSystem::GraphicsMode));
+
+	// Do deep copy. Each can be freed independently of the other.
+	OSystem::GraphicsMode *gm = modes;
+	while (gm->name) {
+		gm->name = strdup(gm->name);
+		gm->description = strdup(gm->description);
+		++gm;
+	}
+
+	return modes;
 }
 
 const OSystem::GraphicsMode *SurfaceSdlGraphicsManager::getSupportedGraphicsModes() const {

backends/platform/sdl/sdl.cpp

@@ -153,6 +153,15 @@ OSystem_SDL::~OSystem_SDL() {
 	delete _mutexManager;
 	_mutexManager = 0;
 
+#ifdef USE_OPENGL
+	for (int i = 0; i < _sdlModesCount; ++i) {
+		// SurfaceSDL needs us to free these
+		free(const_cast<char *>(_graphicsModes[i].name));
+		free(const_cast<char *>(_graphicsModes[i].description));
+	}
+	delete[] _graphicsModes;
+#endif
+
 	delete _logger;
 	_logger = 0;
 
@@ -939,6 +948,9 @@ void OSystem_SDL::setupGraphicsModes() {
 		mode->id = i++;
 		mode++;
 	}
+
+	// SurfaceSDLGraphicsManager expects us to delete[] this
+	delete[] sdlGraphicsModes;
 }
 #endif