Use toml representation to get defaults

Signed-off-by: Evan Lezar <elezar@nvidia.com>

internal/config/config.go

@@ -66,7 +66,7 @@ func GetConfig() (*Config, error) {
 
 	tomlFile, err := os.Open(configFilePath)
 	if err != nil {
-		return getDefaultConfig(), nil
+		return getDefaultConfig()
 	}
 	defer tomlFile.Close()
 
@@ -90,41 +90,53 @@ func loadConfigFrom(reader io.Reader) (*Config, error) {
 
 // getConfigFrom reads the nvidia container runtime config from the specified toml Tree.
 func getConfigFrom(toml *toml.Tree) (*Config, error) {
-	cfg := getDefaultConfig()
-
-	if toml == nil {
-		return cfg, nil
-	}
-
-	cfg.AcceptEnvvarUnprivileged = toml.GetDefault("accept-nvidia-visible-devices-envvar-when-unprivileged", cfg.AcceptEnvvarUnprivileged).(bool)
-
-	cfg.NVIDIAContainerCLIConfig = *getContainerCLIConfigFrom(toml)
-	cfg.NVIDIACTKConfig = *getCTKConfigFrom(toml)
-	runtimeConfig, err := getRuntimeConfigFrom(toml)
+	cfg, err := getDefaultConfig()
 	if err != nil {
-		return nil, fmt.Errorf("failed to load nvidia-container-runtime config: %v", err)
+		return nil, err
 	}
-	cfg.NVIDIAContainerRuntimeConfig = *runtimeConfig
 
-	runtimeHookConfig, err := getRuntimeHookConfigFrom(toml)
-	if err != nil {
-		return nil, fmt.Errorf("failed to load nvidia-container-runtime-hook config: %v", err)
+	if err := toml.Unmarshal(cfg); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal config: %v", err)
 	}
-	cfg.NVIDIAContainerRuntimeHookConfig = *runtimeHookConfig
 
 	return cfg, nil
 }
 
 // getDefaultConfig defines the default values for the config
-func getDefaultConfig() *Config {
-	c := Config{
-		AcceptEnvvarUnprivileged:     true,
-		NVIDIAContainerCLIConfig:     *getDefaultContainerCLIConfig(),
-		NVIDIACTKConfig:              *getDefaultCTKConfig(),
-		NVIDIAContainerRuntimeConfig: *GetDefaultRuntimeConfig(),
+func getDefaultConfig() (*Config, error) {
+	tomlConfig, err := GetDefaultConfigToml()
+	if err != nil {
+		return nil, err
 	}
 
-	return &c
+	// tomlConfig above includes information about the default values and comments.
+	// we need to marshal it back to a string and then unmarshal it to strip the comments.
+	contents, err := tomlConfig.ToTomlString()
+	if err != nil {
+		return nil, err
+	}
+
+	reloaded, err := toml.Load(contents)
+	if err != nil {
+		return nil, err
+	}
+
+	d := Config{}
+	if err := reloaded.Unmarshal(&d); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal config: %v", err)
+	}
+
+	// The default value for the accept-nvidia-visible-devices-envvar-when-unprivileged is non-standard.
+	// As such we explicitly handle it being set here.
+	if reloaded.Get("accept-nvidia-visible-devices-envvar-when-unprivileged") == nil {
+		d.AcceptEnvvarUnprivileged = true
+	}
+	// The default value for the nvidia-container-runtime.debug is non-standard.
+	// As such we explicitly handle it being set here.
+	if reloaded.Get("nvidia-container-runtime.debug") == nil {
+		d.NVIDIAContainerRuntimeConfig.DebugFilePath = "/dev/null"
+	}
+	return &d, nil
 }
 
 // GetDefaultConfigToml returns the default config as a toml Tree.