system76-edk2/MdeModulePkg/Library/ExtendedIfrSupportLib/Common.c

/** @file
  Common Library Routines to assist handle HII elements.

Copyright (c) 2007 - 2008, Intel Corporation. <BR>
All rights reserved. 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 "LibraryInternal.h"


//
// Hii relative protocols
//

EFI_HII_DATABASE_PROTOCOL *gIfrLibHiiDatabase;
EFI_HII_STRING_PROTOCOL   *gIfrLibHiiString;
GLOBAL_REMOVE_IF_UNREFERENCED CONST EFI_GUID mIfrVendorGuid = EFI_IFR_TIANO_GUID;

/**
  ExtendedIfrSupportLib's constructor. It locates the required protocol:
  gEfiHiiDatabaseProtocolGuid and gEfiHiiStringProtocolGuid.

  @param ImageHandle     The firmware allocated handle for the EFI image.
  
  @param SystemTable     A pointer to the EFI System Table.

  @retval EFI_SUCCESS    This function always completes successfully.

**/
EFI_STATUS
EFIAPI
ExtendedIfrSupportLibConstructor (
  IN EFI_HANDLE           ImageHandle,
  IN EFI_SYSTEM_TABLE     *SystemTable
  )
{
  EFI_STATUS  Status;

  Status = gBS->LocateProtocol (&gEfiHiiDatabaseProtocolGuid, NULL, (VOID **) &gIfrLibHiiDatabase);
  ASSERT_EFI_ERROR (Status);

  Status = gBS->LocateProtocol (&gEfiHiiStringProtocolGuid, NULL, (VOID **) &gIfrLibHiiString);
  ASSERT_EFI_ERROR (Status);
  
  return EFI_SUCCESS;
}


/**
  Extract formset class for given HII handle.


  @param Handle          The HII handle.
  @param Class           Class of the formset.
  @param FormSetTitle    Formset title string.
  @param FormSetHelp     Formset help string.

  @retval  EFI_SUCCESS      Successfully extract Class for specified Hii handle.
  @return  Other values if failed to export packages for the given HII handle.

**/
EFI_STATUS
EFIAPI
IfrLibExtractClassFromHiiHandle (
  IN      EFI_HII_HANDLE      Handle,
  OUT     UINT16              *Class,
  OUT     EFI_STRING_ID       *FormSetTitle,
  OUT     EFI_STRING_ID       *FormSetHelp
  )
{
  EFI_STATUS                   Status;
  UINTN                        BufferSize;
  EFI_HII_PACKAGE_LIST_HEADER  *HiiPackageList;
  UINT8                        *Package;
  UINT8                        *OpCodeData;
  UINT32                       Offset;
  UINT32                       Offset2;
  UINT32                       PackageListLength;
  EFI_HII_PACKAGE_HEADER       PackageHeader;

  ASSERT (Handle != NULL);
  ASSERT (Class != NULL);  
  ASSERT (FormSetTitle != NULL);
  ASSERT (FormSetHelp != NULL);

  *Class = EFI_NON_DEVICE_CLASS;
  *FormSetTitle = 0;
  *FormSetHelp = 0;

  //
  // Get HII PackageList
  //
  BufferSize = 0;
  HiiPackageList = NULL;
  Status = gIfrLibHiiDatabase->ExportPackageLists (gIfrLibHiiDatabase, Handle, &BufferSize, HiiPackageList);
  //
  // Handle is a invalid handle. Check if Handle is corrupted.
  //
  ASSERT (Status != EFI_NOT_FOUND);
  //
  // The return status should always be EFI_BUFFER_TOO_SMALL as input buffer's size is 0.
  //
  ASSERT (Status == EFI_BUFFER_TOO_SMALL);
  
  HiiPackageList = AllocatePool (BufferSize);
  ASSERT (HiiPackageList != NULL);

  Status = gIfrLibHiiDatabase->ExportPackageLists (gIfrLibHiiDatabase, Handle, &BufferSize, HiiPackageList);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  //
  // Get Form package from this HII package List
  //
  Offset = sizeof (EFI_HII_PACKAGE_LIST_HEADER);
  Offset2 = 0;
  PackageListLength = ReadUnaligned32 (&HiiPackageList->PackageLength);

  while (Offset < PackageListLength) {
    Package = ((UINT8 *) HiiPackageList) + Offset;
    CopyMem (&PackageHeader, Package, sizeof (EFI_HII_PACKAGE_HEADER));

    if (PackageHeader.Type == EFI_HII_PACKAGE_FORMS) {
      //
      // Search Class Opcode in this Form Package
      //
      Offset2 = sizeof (EFI_HII_PACKAGE_HEADER);
      while (Offset2 < PackageHeader.Length) {
        OpCodeData = Package + Offset2;

        if (((EFI_IFR_OP_HEADER *) OpCodeData)->OpCode == EFI_IFR_FORM_SET_OP) {
          //
          // Find FormSet OpCode
          //
          CopyMem (FormSetTitle, &((EFI_IFR_FORM_SET *) OpCodeData)->FormSetTitle, sizeof (EFI_STRING_ID));
          CopyMem (FormSetHelp, &((EFI_IFR_FORM_SET *) OpCodeData)->Help, sizeof (EFI_STRING_ID));
        }

        if ((((EFI_IFR_OP_HEADER *) OpCodeData)->OpCode == EFI_IFR_GUID_OP) &&
             CompareGuid (&mIfrVendorGuid, (EFI_GUID *)(OpCodeData + sizeof (EFI_IFR_OP_HEADER))) &&
            (((EFI_IFR_GUID_CLASS *) OpCodeData)->ExtendOpCode == EFI_IFR_EXTEND_OP_CLASS)
           ) {
          //
          // Find GUIDed Class OpCode
          //
          CopyMem (Class, &((EFI_IFR_GUID_CLASS *) OpCodeData)->Class, sizeof (UINT16));

          //
          // Till now, we ought to have found the formset Opcode
          //
          break;
        }

        Offset2 += ((EFI_IFR_OP_HEADER *) OpCodeData)->Length;
      }

      if (Offset2 < PackageHeader.Length) {
        //
        // Target formset found
        //
        break;
      }
    }

    Offset += PackageHeader.Length;
  }

  FreePool (HiiPackageList);

  return EFI_SUCCESS;
}