HiiLibGetCurrentLanguage returns the current UEFI variable "PlatformLang" (if this variable does not exist, a default value is returned). This function is called by HiiDatabase itself. Now, HiiLibGetCurrentLanguage is in HiiLib. Because of this, we can't add location of Hii protoocol in the library constructor of HiiLib. This cause Hii Database driver never get loaded (circular dependency).

By moving HiiLibGetCurrentLanguage to UefiLib, library constructor (depex) can be added back to HiiLib to make sure the execution order is correct.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5938 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Include/Library/UefiLib.h

@@ -22,6 +22,12 @@
 #include <Protocol/DriverDiagnostics.h>
 #include <Protocol/DriverDiagnostics2.h>
 
+///
+/// Limited buffer size recommended by RFC3066
+/// (42 characters plus a NULL terminator)
+///
+#define RFC_3066_ENTRY_SIZE             (42 + 1)
+
 ///
 /// Unicode String Table
 ///
@@ -986,4 +992,26 @@ EfiLibInstallAllDriverProtocols2 (
   IN CONST EFI_DRIVER_DIAGNOSTICS2_PROTOCOL   *DriverDiagnostics2   OPTIONAL
   );
 
+/**
+  Determine what is the current language setting. The space reserved for Lang
+  must be at least RFC_3066_ENTRY_SIZE bytes;
+
+  If Lang is NULL, then ASSERT.
+
+  @param  Lang                   Pointer of system language. Lang will always be filled with 
+                                         a valid RFC 3066 language string. If "PlatformLang" is not
+                                         set in the system, the default language specifed by PcdUefiVariableDefaultPlatformLang
+                                         is returned.
+
+  @return  EFI_SUCCESS     If the EFI Variable with "PlatformLang" is set and return in Lang.
+  @return  EFI_NOT_FOUND If the EFI Variable with "PlatformLang" is not set, but a valid default language is return in Lang.
+
+**/
+EFI_STATUS
+EFIAPI
+GetCurrentLanguage (
+  OUT     CHAR8               *Lang
+  );
+
+
 #endif