FEXCore: Fixes priority of FEX_APP_CONFIG

This environment variable had an incorrect priority on the configuration system. The expectation was higher priority than most other layers. Now the only layer that has higher priority is the environment variables.
FEX-Emu · Apr 5, 2024 · 02b144a · 02b144a
1 parent 202a60b
commit 02b144a
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Showing 5 changed files with 28 additions and 16 deletions.
diff --git a/FEXCore/Source/Interface/Config/Config.cpp b/FEXCore/Source/Interface/Config/Config.cpp
@@ -130,14 +130,15 @@ namespace DefaultValues {
   static fextl::map<FEXCore::Config::LayerType, fextl::unique_ptr<FEXCore::Config::Layer>> ConfigLayers;
   static FEXCore::Config::Layer *Meta{};
 
-  constexpr std::array<FEXCore::Config::LayerType, 9> LoadOrder = {
+  constexpr std::array<FEXCore::Config::LayerType, 10> LoadOrder = {
     FEXCore::Config::LayerType::LAYER_GLOBAL_MAIN,
     FEXCore::Config::LayerType::LAYER_MAIN,
     FEXCore::Config::LayerType::LAYER_GLOBAL_STEAM_APP,
     FEXCore::Config::LayerType::LAYER_GLOBAL_APP,
     FEXCore::Config::LayerType::LAYER_LOCAL_STEAM_APP,
     FEXCore::Config::LayerType::LAYER_LOCAL_APP,
     FEXCore::Config::LayerType::LAYER_ARGUMENTS,
+    FEXCore::Config::LayerType::LAYER_USER_OVERRIDE,
     FEXCore::Config::LayerType::LAYER_ENVIRONMENT,
     FEXCore::Config::LayerType::LAYER_TOP
   };

diff --git a/FEXCore/include/FEXCore/Config/Config.h b/FEXCore/include/FEXCore/Config/Config.h
@@ -81,6 +81,7 @@ namespace Handler {
     LAYER_GLOBAL_APP,
     LAYER_LOCAL_STEAM_APP,
     LAYER_LOCAL_APP,
+    LAYER_USER_OVERRIDE,
     LAYER_ENVIRONMENT,
     LAYER_TOP,
   };

diff --git a/Source/Common/Config.cpp b/Source/Common/Config.cpp
@@ -129,6 +129,8 @@ namespace JSON {
   public:
     explicit MainLoader(FEXCore::Config::LayerType Type);
     explicit MainLoader(fextl::string ConfigFile);
+    explicit MainLoader(FEXCore::Config::LayerType Type, const char* ConfigFile);
+
     void Load() override;
 
   private:
@@ -188,6 +190,12 @@ namespace JSON {
     , Config{std::move(ConfigFile)} {
   }
 
+
+  MainLoader::MainLoader(FEXCore::Config::LayerType Type, const char* ConfigFile)
+    : OptionMapper(Type)
+    , Config{std::move(ConfigFile)} {
+  }
+
   void MainLoader::Load() {
     JSON::LoadJSonConfig(Config, [this](const char *Name, const char *ConfigString) {
       MapNameToOption(Name, ConfigString);
@@ -276,6 +284,10 @@ namespace JSON {
     }
   }
 
+  fextl::unique_ptr<FEXCore::Config::Layer> CreateUserOverrideLayer(const char* AppConfig) {
+    return fextl::make_unique<MainLoader>(FEXCore::Config::LayerType::LAYER_USER_OVERRIDE, AppConfig);
+  }
+
   fextl::unique_ptr<FEXCore::Config::Layer> CreateAppLayer(const fextl::string& Filename, FEXCore::Config::LayerType Type) {
     return fextl::make_unique<AppLoader>(Filename, Type);
   }
@@ -371,6 +383,11 @@ namespace JSON {
       FEXCore::Config::AddLayer(fextl::make_unique<FEX::ArgLoader::ArgLoader>(argc, argv));
     }
 
+    const char *AppConfig = getenv("FEX_APP_CONFIG");
+    if (AppConfig && FHU::Filesystem::Exists(AppConfig)) {
+      FEXCore::Config::AddLayer(CreateUserOverrideLayer(AppConfig));
+    }
+
     FEXCore::Config::AddLayer(CreateEnvironmentLayer(envp));
     FEXCore::Config::Load();
 
@@ -529,21 +546,7 @@ namespace JSON {
   }
 
   fextl::string GetConfigFileLocation(bool Global) {
-    fextl::string ConfigFile{};
-    if (Global) {
-      ConfigFile = GetConfigDirectory(true) + "Config.json";
-    }
-    else {
-      const char *AppConfig = getenv("FEX_APP_CONFIG");
-      if (AppConfig) {
-        // App config environment variable overwrites only the config file
-        ConfigFile = AppConfig;
-      }
-      else {
-        ConfigFile = GetConfigDirectory(false) + "Config.json";
-      }
-    }
-    return ConfigFile;
+    return GetConfigDirectory(Global) + "Config.json";
   }
 
   void InitializeConfigs() {

diff --git a/Source/Common/Config.h b/Source/Common/Config.h
@@ -73,6 +73,7 @@ namespace FEX::Config {
    * @return unique_ptr for that layer
    */
   fextl::unique_ptr<FEXCore::Config::Layer> CreateMainLayer(fextl::string const *File = nullptr);
+  fextl::unique_ptr<FEXCore::Config::Layer> CreateUserOverrideLayer(const char* AppConfig);
 
   /**
    * @brief Create an application configuration loader

diff --git a/Source/Tools/LinuxEmulation/LinuxSyscalls/FileManagement.cpp b/Source/Tools/LinuxEmulation/LinuxSyscalls/FileManagement.cpp
@@ -219,6 +219,7 @@ FileManager::FileManager(FEXCore::Context::Context *ctx)
   // - AppConfig Global
   // - Steam AppConfig Local
   // - AppConfig Local
+  // - AppConfig override
   // This doesn't support the classic thunks interface.
 
   auto AppName = AppConfigName();
@@ -245,6 +246,11 @@ FileManager::FileManager(FEXCore::Context::Context *ctx)
     ConfigPaths.emplace_back(FEXCore::Config::GetApplicationConfig(AppName, false));
   }
 
+  const char *AppConfig = getenv("FEX_APP_CONFIG");
+  if (AppConfig) {
+    ConfigPaths.emplace_back(AppConfig);
+  }
+
   if (!LDPath().empty()) {
     RootFSFD = open(LDPath().c_str(), O_DIRECTORY | O_PATH | O_CLOEXEC);
     if (RootFSFD == -1) {