MdeModulePkg: Make HII configuration settings available to OS runtime

This feature is aimed to allow OS make use of the HII database
during runtime. In this case, the contents of the HII Database
is exported to a buffer. The pointer to the buffer is placed
in the EFI System Configuration Table, where it can be retrieved
by an OS application.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Brian J. Johnson <bjohnson@sgi.com>
Cc: Andrew Fish <afish@apple.com>
Cc: El-Haj-Mahmoud Samer <samer.el-haj-mahmoud@hpe.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>

MdeModulePkg/Universal/HiiDatabaseDxe/HiiDatabase.h

@@ -2017,8 +2017,38 @@ GetSupportedLanguages (
   IN EFI_HII_HANDLE           HiiHandle
   );
 
+/**
+This function mainly use to get HiiDatabase information.
+
+@param  This                   A pointer to the EFI_HII_DATABASE_PROTOCOL instance.
+
+@retval EFI_SUCCESS            Get the information successfully.
+@retval EFI_OUT_OF_RESOURCES   Not enough memory to store the Hiidatabase data.
+
+**/
+EFI_STATUS
+HiiGetDatabaseInfo(
+  IN CONST EFI_HII_DATABASE_PROTOCOL        *This
+  );
+
+/**
+This is an internal function,mainly use to get and update configuration settings information.
+
+@param  This                   A pointer to the EFI_HII_DATABASE_PROTOCOL instance.
+
+@retval EFI_SUCCESS            Get the information successfully.
+@retval EFI_OUT_OF_RESOURCES   Not enough memory to store the Configuration Setting data.
+
+**/
+EFI_STATUS
+HiiGetConfigurationSetting(
+  IN CONST EFI_HII_DATABASE_PROTOCOL        *This
+  );
+
 //
 // Global variables
 //
 extern EFI_EVENT gHiiKeyboardLayoutChanged;
+extern BOOLEAN   gExportAfterReadyToBoot;
+
 #endif