MdeModulePkg/Library/UefiHiiServicesLib/UefiHiiServicesLib.c

   1 /** @file
   2   This library retrieves pointers to the UEFI HII Protocol instances in the
   3   library's constructor.  All of the UEFI HII related protocols are optional,
   4   so the consumers of this library class must verify that the global variable
   5   pointers are not NULL before use.
   6
   7   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   8   SPDX-License-Identifier: BSD-2-Clause-Patent
   9
  10 **/
  11
  12 #include <Uefi.h>
  13
  14 #include <Library/UefiHiiServicesLib.h>
  15 #include <Library/UefiBootServicesTableLib.h>
  16 #include <Library/DebugLib.h>
  17
  18 #include <Protocol/HiiFont.h>
  19 #include <Protocol/HiiString.h>
  20 #include <Protocol/HiiImage.h>
  21 #include <Protocol/HiiDatabase.h>
  22 #include <Protocol/HiiConfigRouting.h>
  23
  24 ///
  25 /// Pointer to the UEFI HII Font Protocol
  26 ///
  27 EFI_HII_FONT_PROTOCOL  *gHiiFont = NULL;
  28
  29 ///
  30 /// Pointer to the UEFI HII String Protocol
  31 ///
  32 EFI_HII_STRING_PROTOCOL  *gHiiString = NULL;
  33
  34 ///
  35 /// Pointer to the UEFI HII Image Protocol
  36 ///
  37 EFI_HII_IMAGE_PROTOCOL  *gHiiImage = NULL;
  38
  39 ///
  40 /// Pointer to the UEFI HII Database Protocol
  41 ///
  42 EFI_HII_DATABASE_PROTOCOL  *gHiiDatabase = NULL;
  43
  44 ///
  45 /// Pointer to the UEFI HII Config Rounting Protocol
  46 ///
  47 EFI_HII_CONFIG_ROUTING_PROTOCOL  *gHiiConfigRouting = NULL;
  48
  49 /**
  50   The constructor function retrieves pointers to the UEFI HII protocol instances
  51
  52   The constructor function retrieves pointers to the four UEFI HII protocols from the
  53   handle database.  These include the UEFI HII Font Protocol, the UEFI HII String
  54   Protocol, the UEFI HII Image Protocol, the UEFI HII Database Protocol, and the
  55   UEFI HII Config Routing Protocol.  This function always return EFI_SUCCESS.
  56   All of these protocols are optional if the platform does not support configuration
  57   and the UEFI HII Image Protocol and the UEFI HII Font Protocol are optional if
  58   the platform does not support a graphical console.  As a result, the consumers
  59   of this library much check the protocol pointers againt NULL before using them,
  60   or use dependency expressions to guarantee that some of them are present before
  61   assuming they are not NULL.
  62
  63   @param  ImageHandle   The firmware allocated handle for the EFI image.
  64   @param  SystemTable   A pointer to the EFI System Table.
  65
  66   @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.
  67
  68 **/
  69 EFI_STATUS
  70 EFIAPI
  71 UefiHiiServicesLibConstructor (
  72   IN EFI_HANDLE        ImageHandle,
  73   IN EFI_SYSTEM_TABLE  *SystemTable
  74   )
  75 {
  76   EFI_STATUS  Status;
  77
  78   //
  79   // Retrieve the pointer to the UEFI HII String Protocol
  80   //
  81   Status = gBS->LocateProtocol (&gEfiHiiStringProtocolGuid, NULL, (VOID **)&gHiiString);
  82   ASSERT_EFI_ERROR (Status);
  83
  84   //
  85   // Retrieve the pointer to the UEFI HII Database Protocol
  86   //
  87   Status = gBS->LocateProtocol (&gEfiHiiDatabaseProtocolGuid, NULL, (VOID **)&gHiiDatabase);
  88   ASSERT_EFI_ERROR (Status);
  89
  90   //
  91   // Retrieve the pointer to the UEFI HII Config Routing Protocol
  92   //
  93   Status = gBS->LocateProtocol (&gEfiHiiConfigRoutingProtocolGuid, NULL, (VOID **)&gHiiConfigRouting);
  94   ASSERT_EFI_ERROR (Status);
  95
  96   //
  97   // Retrieve the pointer to the optional UEFI HII Font Protocol
  98   //
  99   gBS->LocateProtocol (&gEfiHiiFontProtocolGuid, NULL, (VOID **)&gHiiFont);
 100
 101   //
 102   // Retrieve the pointer to the optional UEFI HII Image Protocol
 103   //
 104   gBS->LocateProtocol (&gEfiHiiImageProtocolGuid, NULL, (VOID **)&gHiiImage);
 105
 106   return EFI_SUCCESS;
 107 }