From 0a9c3a2614ce97cba42788fc5432c4f36a9216b5 Mon Sep 17 00:00:00 2001
From: Antoine Pilote <antoinepilote1@hotmail.com>
Date: Mon, 2 Oct 2023 01:32:49 -0400
Subject: [PATCH] Fixed memory leak in wren scriptign engine

---
 Nuake/src/Scripting/ScriptingEngine.cpp | 45 +++++++++++++------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/Nuake/src/Scripting/ScriptingEngine.cpp b/Nuake/src/Scripting/ScriptingEngine.cpp
index 70a1557b..9b2df383 100644
--- a/Nuake/src/Scripting/ScriptingEngine.cpp
+++ b/Nuake/src/Scripting/ScriptingEngine.cpp
@@ -19,20 +19,20 @@ namespace Nuake {
     std::vector<std::string> ScriptingEngine::m_LoadedScripts;
 
     void errorFn(WrenVM* vm, WrenErrorType errorType,
-        const char* module, const int line,
+        const char* moduleName, const int line,
         const char* msg)
     {
         switch (errorType)
         {
         case WREN_ERROR_COMPILE:
         {
-            std::string t = std::string(module) + " line " + std::to_string(line) + ": " + msg;
+            std::string t = std::string(moduleName) + " line " + std::to_string(line) + ": " + msg;
             Logger::Log(t, "script", CRITICAL);
             Engine::ExitPlayMode();
         } break;
         case WREN_ERROR_STACK_TRACE:
         {
-            std::string t = "Stack trace: " + std::string(module) + " line " + std::to_string(line) + ": " + msg;
+            std::string t = "Stack trace: " + std::string(moduleName) + " line " + std::to_string(line) + ": " + msg;
             Logger::Log(t, "script", CRITICAL);
         } break;
         case WREN_ERROR_RUNTIME:
@@ -70,20 +70,26 @@ namespace Nuake {
 
     std::map<std::string, std::string> _ModulesSRC =
     {
-        {"Audio", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Audio_wren)},
-        {"Engine", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Engine_wren)},
-        {"Input", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Input_wren)},
-        {"Math", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Math_wren)},
-        {"Physics", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Physics_wren)},
-        {"Scene", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Scene_wren)},
-        {"ScriptableEntity", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_ScriptableEntity_wren)},
+        { "Audio", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Audio_wren) },
+        { "Engine", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Engine_wren) },
+        { "Input", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Input_wren) },
+        { "Math", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Math_wren) },
+        { "Physics", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Physics_wren) },
+        { "Scene", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_Scene_wren) },
+        { "ScriptableEntity", GET_STATIC_RESOURCE_SCRIPT_SRC(StaticResources::Resources_Scripts_ScriptableEntity_wren) },
     };
 
+    void onCompleteCB(WrenVM* vm, const char* name, WrenLoadModuleResult result)
+    {
+        delete result.source;
+    }
+
     const std::string NuakeModulePrefix = "Nuake:";
     WrenLoadModuleResult myLoadModule(WrenVM* vm, const char* name)
     {
         WrenLoadModuleResult result = { 0 };
 
+        result.onComplete = &onCompleteCB; // This will take care of the clean up of the new char*
         std::string sname = std::string(name);
         std::string path = "resources/" + std::string(name);
 
@@ -118,7 +124,9 @@ namespace Nuake {
             fileContent = FileSystem::ReadFile(path, true);
         }
 
-        char* c = strcpy(new char[fileContent.length() + 1], fileContent.c_str());
+        // We have to use c style char array and the callback takes care of cleaning up.
+        char* sourceC = new char[fileContent.length() + 1];
+        char* c = strcpy(sourceC, fileContent.c_str()); // copy into c array
 
         result.source = c;
         return result;
@@ -193,16 +201,11 @@ namespace Nuake {
         m_WrenVM = wrenNewVM(&config);
 
         Logger::Log("Registing Scripting Modules");
-        Ref<ScriptAPI::EngineModule> engineModule = CreateRef<ScriptAPI::EngineModule>();
-        RegisterModule(engineModule);
-        Ref<ScriptAPI::SceneModule> sceneModule = CreateRef<ScriptAPI::SceneModule>();
-        RegisterModule(sceneModule);
-        Ref<ScriptAPI::MathModule> mathModule = CreateRef<ScriptAPI::MathModule>();
-        RegisterModule(mathModule);
-        Ref<ScriptAPI::InputModule> inputModule = CreateRef<ScriptAPI::InputModule>();
-        RegisterModule(inputModule);
-        Ref<ScriptAPI::PhysicsModule> physicsModule = CreateRef<ScriptAPI::PhysicsModule>();
-        RegisterModule(physicsModule);
+        RegisterModule(CreateRef<ScriptAPI::EngineModule>());
+        RegisterModule(CreateRef<ScriptAPI::SceneModule>());
+        RegisterModule(CreateRef<ScriptAPI::MathModule>());
+        RegisterModule(CreateRef<ScriptAPI::InputModule>());
+        RegisterModule(CreateRef<ScriptAPI::PhysicsModule>());
         Logger::Log("Scripting Modules Registered");
         Logger::Log("Scripting Engine initialized successfully");
     }