Fix per-game config values leaking across titles

src/xenia/base/cvar.h

@@ -50,6 +50,7 @@ class IConfigVar : virtual public ICommandVar {
   virtual std::string config_value() const = 0;
   virtual void LoadConfigValue(std::shared_ptr<cpptoml::base> result) = 0;
   virtual void LoadGameConfigValue(std::shared_ptr<cpptoml::base> result) = 0;
+  virtual void ResetGameConfigValue() = 0;
   virtual void ResetConfigValueToDefault() = 0;
 };
 
@@ -95,6 +96,7 @@ class ConfigVar : public CommandVar<T>, virtual public IConfigVar {
   // one that will be stored when the global config is written next time. After
   // overriding, however, the next game config loaded may still change it.
   void OverrideConfigValue(T val);
+  void ResetGameConfigValue() override;
 
  private:
   std::string category_;
@@ -278,6 +280,13 @@ void ConfigVar<T>::OverrideConfigValue(T val) {
   this->commandline_value_.reset();
   UpdateValue();
 }
+
+template <class T>
+void ConfigVar<T>::ResetGameConfigValue() {
+  game_config_value_.reset();
+  UpdateValue();
+}
+
 template <class T>
 void ConfigVar<T>::ResetConfigValueToDefault() {
   SetConfigValue(this->default_value_);

src/xenia/config.cc

@@ -104,6 +104,16 @@ void ReadGameConfig(const std::filesystem::path& file_path) {
   XELOGI("Loaded game config: {}", xe::path_to_utf8(file_path));
 }
 
+void ResetGameConfigValues() {
+  if (!cvar::ConfigVars) {
+    return;
+  }
+  for (auto& it : *cvar::ConfigVars) {
+    auto config_var = static_cast<cvar::IConfigVar*>(it.second);
+    config_var->ResetGameConfigValue();
+  }
+}
+
 void SaveConfig() {
   if (config_path.empty()) {
     return;
@@ -238,6 +248,8 @@ void SetupConfig(const std::filesystem::path& config_folder) {
 }
 
 void LoadGameConfig(const std::string_view title_id) {
+  ResetGameConfigValues();
+
   const auto game_config_folder = config_folder / "config";
   const auto game_config_path =
       game_config_folder / (std::string(title_id) + game_config_suffix);