1 files changed, 68 insertions, 0 deletions
diff --git a/Core/MdePkg/Library/DxeServicesTableLib/DxeServicesTableLib.c b/Core/MdePkg/Library/DxeServicesTableLib/DxeServicesTableLib.c
new file mode 100644
index 0000000000..7cb94cee70
--- /dev/null
+++ b/Core/MdePkg/Library/DxeServicesTableLib/DxeServicesTableLib.c
@@ -0,0 +1,68 @@
+/** @file
+  This library implement library class DxeServiceTableLib.
+  It produce EFI_DXE_SERVICE pointer in global variable gDS in library's constructure.
+  
+  A DXE driver can use gDS pointer to access services in EFI_DXE_SERVICE, if this
+  DXE driver declare that use DxeServicesTableLib library class and link to this 
+  library instance.
+
+  Please attention this library instance can not be used util EFI_SYSTEM_TABLE was 
+  initialized.
+  
+  This library contains contruct function to retrieve EFI_DXE_SERIVCE, this construct
+  function will be invoked in DXE driver's autogen file.
+
+  Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php.
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include <PiDxe.h>
+#include <Guid/DxeServices.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/DebugLib.h>
+#include <Library/UefiLib.h>
+
+//
+// Cache copy of the DXE Services Table
+//
+EFI_DXE_SERVICES  *gDS      = NULL;
+
+/**
+  The constructor function caches the pointer of DXE Services Table.
+
+  The constructor function caches the pointer of DXE Services Table.
+  It will ASSERT() if that operation fails.
+  It will ASSERT() if the pointer of DXE Services Table is NULL.
+  It will always return EFI_SUCCESS.
+
+  @param  ImageHandle   The firmware allocated handle for the EFI image.
+  @param  SystemTable   A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.
+
+**/
+EFI_STATUS
+EFIAPI
+DxeServicesTableLibConstructor (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  EFI_STATUS  Status;
+
+  //
+  // Cache copy of the DXE Services Table
+  //
+  Status = EfiGetSystemConfigurationTable (&gEfiDxeServicesTableGuid, (VOID **) &gDS);
+  ASSERT_EFI_ERROR (Status);
+  ASSERT (gDS != NULL);
+
+  return Status;
+}