Codechange: Use unique_ptr for all pointers in script instance.

Removes manual memory management with new/delete.

src/ai/ai_instance.cpp

@@ -43,7 +43,7 @@ void AIInstance::Initialize(AIInfo *info)
 	this->api_version = info->GetAPIVersion();
 
 	/* Register the AIController (including the "import" command) */
-	SQAIController_Register(*this->engine);
+	SQAIController_Register(this->GetEngine());
 
 	ScriptInstance::Initialize(info->GetMainScript(), info->GetInstanceName(), _current_company);
 }
@@ -53,7 +53,7 @@ void AIInstance::RegisterAPI()
 	ScriptInstance::RegisterAPI();
 
 	/* Register all classes */
-	SQAI_RegisterAll(*this->engine);
+	SQAI_RegisterAll(this->GetEngine());
 
 	if (!this->LoadCompatibilityScripts(AI_DIR, AIInfo::ApiVersions)) this->Died();
 }
@@ -83,8 +83,8 @@ void AIInstance::Died()
 
 void AIInstance::LoadDummyScript()
 {
-	ScriptAllocatorScope alloc_scope(this->engine);
-	Script_CreateDummy(this->engine->GetVM(), STR_ERROR_AI_NO_AI_FOUND, "AI");
+	ScriptAllocatorScope alloc_scope(&this->GetEngine());
+	Script_CreateDummy(this->GetEngine().GetVM(), STR_ERROR_AI_NO_AI_FOUND, "AI");
 }
 
 int AIInstance::GetSetting(const std::string &name)

src/game/game_instance.cpp

@@ -38,7 +38,7 @@ void GameInstance::Initialize(GameInfo *info)
 	this->api_version = info->GetAPIVersion();
 
 	/* Register the GameController */
-	SQGSController_Register(*this->engine);
+	SQGSController_Register(this->GetEngine());
 
 	ScriptInstance::Initialize(info->GetMainScript(), info->GetInstanceName(), OWNER_DEITY);
 }
@@ -48,11 +48,11 @@ void GameInstance::RegisterAPI()
 	ScriptInstance::RegisterAPI();
 
 	/* Register all classes */
-	SQGS_RegisterAll(*this->engine);
+	SQGS_RegisterAll(this->GetEngine());
 
 	if (!this->LoadCompatibilityScripts(GAME_DIR, GameInfo::ApiVersions)) this->Died();
 
-	if (this->IsAlive()) RegisterGameTranslation(*this->engine);
+	if (this->IsAlive()) RegisterGameTranslation(this->GetEngine());
 }
 
 int GameInstance::GetSetting(const std::string &name)

src/script/api/script_object.cpp

@@ -53,7 +53,7 @@ static ScriptStorage &GetStorage()
 
 /* static */ ScriptInstance *ScriptObject::ActiveInstance::active = nullptr;
 
-ScriptObject::ActiveInstance::ActiveInstance(ScriptInstance &instance) : alc_scope(instance.engine)
+ScriptObject::ActiveInstance::ActiveInstance(ScriptInstance &instance) : alc_scope(instance.engine.get())
 {
 	this->last_active = ScriptObject::ActiveInstance::active;
 	ScriptObject::ActiveInstance::active = &instance;
@@ -230,8 +230,8 @@ ScriptObject::DisableDoCommandScope::DisableDoCommandScope()
 
 /* static */ bool ScriptObject::CanSuspend()
 {
-	Squirrel *squirrel = ScriptObject::GetActiveInstance().engine;
-	return GetStorage().allow_do_command && squirrel->CanSuspend();
+	Squirrel &squirrel = *ScriptObject::GetActiveInstance().engine;
+	return GetStorage().allow_do_command && squirrel.CanSuspend();
 }
 
 /* static */ ScriptEventQueue &ScriptObject::GetEventQueue()

src/script/script_instance.cpp

@@ -47,9 +47,8 @@ static void PrintFunc(bool error_msg, std::string_view message)
 }
 
 ScriptInstance::ScriptInstance(std::string_view api_name)
+		: storage(std::make_unique<ScriptStorage>()), engine(std::make_unique<Squirrel>(api_name))
 {
-	this->storage = new ScriptStorage();
-	this->engine  = new Squirrel(api_name);
 	this->engine->SetPrintFunction(&PrintFunc);
 }
 
@@ -57,10 +56,10 @@ void ScriptInstance::Initialize(const std::string &main_script, const std::strin
 {
 	ScriptObject::ActiveInstance active(*this);
 
-	this->controller = new ScriptController(company);
+	this->controller = std::make_unique<ScriptController>(company);
 
 	/* Register the API functions and classes */
-	this->engine->SetGlobalPointer(this->engine);
+	this->engine->SetGlobalPointer(this->engine.get());
 	this->RegisterAPI();
 	if (this->IsDead()) {
 		/* Failed to register API; a message has already been logged. */
@@ -79,12 +78,11 @@ void ScriptInstance::Initialize(const std::string &main_script, const std::strin
 		}
 
 		/* Create the main-class */
-		this->instance = new SQObject();
-		if (!this->engine->CreateClassInstance(instance_name, this->controller, this->instance)) {
+		this->instance = std::make_unique<SQObject>();
+		if (!this->engine->CreateClassInstance(instance_name, this->controller.get(), this->instance.get())) {
 			/* If CreateClassInstance has returned false instance has not been
 			 * registered with squirrel, so avoid trying to Release it by clearing it now */
-			delete this->instance;
-			this->instance = nullptr;
+			this->instance.reset();
 			this->Died();
 			return;
 		}
@@ -144,11 +142,10 @@ ScriptInstance::~ScriptInstance()
 	ScriptObject::ActiveInstance active(*this);
 	this->in_shutdown = true;
 
-	if (instance != nullptr) this->engine->ReleaseObject(this->instance);
-	if (engine != nullptr) delete this->engine;
-	delete this->storage;
-	delete this->controller;
-	delete this->instance;
+	if (instance != nullptr) this->engine->ReleaseObject(this->instance.get());
+
+	/* Engine must be reset explicitly as object destruction requires the instance to exist. */
+	this->engine.reset();
 }
 
 void ScriptInstance::Continue()
@@ -165,11 +162,9 @@ void ScriptInstance::Died()
 
 	this->last_allocated_memory = this->GetAllocatedMemory(); // Update cache
 
-	if (this->instance != nullptr) this->engine->ReleaseObject(this->instance);
-	delete this->instance;
-	delete this->engine;
-	this->instance = nullptr;
-	this->engine = nullptr;
+	if (this->instance != nullptr) this->engine->ReleaseObject(this->instance.get());
+	this->engine.reset();
+	this->instance.reset();
 }
 
 void ScriptInstance::GameLoop()

src/script/script_instance.hpp

@@ -256,7 +256,6 @@ public:
 	void ReleaseSQObject(HSQOBJECT *obj);
 
 protected:
-	class Squirrel *engine = nullptr; ///< A wrapper around the squirrel vm.
 	std::string api_version{}; ///< Current API used by this script.
 
 	/**
@@ -287,10 +286,20 @@ protected:
 	 */
 	virtual void LoadDummyScript() = 0;
 
+	/**
+	 * Get the storage of this script.
+	 */
+	inline class Squirrel &GetEngine()
+	{
+		assert(this->engine != nullptr);
+		return *this->engine;
+	}
+
 private:
-	class ScriptController *controller = nullptr; ///< The script main class.
-	class ScriptStorage *storage = nullptr; ///< Some global information for each running script.
-	SQObject *instance = nullptr; ///< Squirrel-pointer to the script main class.
+	std::unique_ptr<class ScriptStorage> storage; ///< Some global information for each running script.
+	std::unique_ptr<class Squirrel> engine; ///< A wrapper around the squirrel vm.
+	std::unique_ptr<class ScriptController> controller; ///< The script main class.
+	std::unique_ptr<SQObject> instance; ///< Squirrel-pointer to the script main class.
 
 	bool is_started = false; ///< Is the scripts constructor executed?
 	bool is_dead = false; ///< True if the script has been stopped.