config/Global: add GetGlobalConfig()

src/config/Global.cxx

@@ -44,6 +44,12 @@ void config_global_init(void)
 {
 }
 
+const ConfigData &
+GetGlobalConfig() noexcept
+{
+	return config_data;
+}
+
 void
 ReadConfigFile(Path path)
 {

src/config/Global.hxx

@@ -27,6 +27,7 @@
 
 class Path;
 class AllocatedPath;
+struct ConfigData;
 struct ConfigParam;
 struct ConfigBlock;
 
@@ -36,6 +37,10 @@ config_global_init();
 void
 config_global_finish();
 
+gcc_const
+const ConfigData &
+GetGlobalConfig() noexcept;
+
 /**
  * Call this function after all configuration has been evaluated.  It
  * checks for unused parameters, and logs warnings.