EdkCompatibilityPkg/Compatibility/ReadOnlyVariableOnReadOnlyVariable2Thunk/ReadOnlyVariableToReadOnlyVariable2Thunk.c

   1 /** @file
   2 Module produce EFI_PEI_READ_ONLY_VARIABLE_PPI on top of EFI_PEI_READ_ONLY_VARIABLE2_PPI.
   3 UEFI PI Spec supersedes Intel's Framework Specs.
   4 # EFI_PEI_READ_ONLY_VARIABLE_PPI defined in Intel Framework Pkg is replaced by EFI_PEI_READ_ONLY_VARIABLE2_PPI
   5 # in MdePkg.
   6 # This module produces EFI_PEI_READ_ONLY_VARIABLE_PPI on top of EFI_PEI_READ_ONLY_VARIABLE2_PPI.
   7 # This module is used on platform when both of these two conditions are true:
   8 # 1) Framework module consumes EFI_PEI_READ_ONLY_VARIABLE_PPI is present.
   9 # 2) The platform has a PI module that only produces EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  10
  11 This module can't be used together with ReadOnlyVariable2ToReadOnlyVariableThunk module.
  12
  13 Copyright (c) 2006 - 2008 Intel Corporation. <BR>
  14 All rights reserved. This program and the accompanying materials
  15 are licensed and made available under the terms and conditions of the BSD License
  16 which accompanies this distribution.  The full text of the license may be found at
  17 http://opensource.org/licenses/bsd-license.php
  18
  19 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  20 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  21 Module Name:
  22
  23 **/
  24
  25 #include <PiPei.h>
  26 #include <Ppi/ReadOnlyVariable.h>
  27 #include <Ppi/ReadOnlyVariable2.h>
  28 #include <Ppi/ReadOnlyVariableThunkPresent.h>
  29 #include <Library/DebugLib.h>
  30 #include <Library/PeiServicesLib.h>
  31
  32 //
  33 // Function Prototypes
  34 //
  35 EFI_STATUS
  36 EFIAPI
  37 PeiGetVariable (
  38   IN  EFI_PEI_SERVICES  **PeiServices,
  39   IN  CHAR16            *VariableName,
  40   IN  EFI_GUID          *VendorGuid,
  41   OUT UINT32            *Attributes OPTIONAL,
  42   IN  OUT UINTN         *DataSize,
  43   OUT VOID              *Data
  44   );
  45
  46 EFI_STATUS
  47 EFIAPI
  48 PeiGetNextVariableName (
  49   IN EFI_PEI_SERVICES  **PeiServices,
  50   IN OUT UINTN         *VariableNameSize,
  51   IN OUT CHAR16        *VariableName,
  52   IN OUT EFI_GUID      *VendorGuid
  53   );
  54
  55 //
  56 // Module globals
  57 //
  58 EFI_PEI_READ_ONLY_VARIABLE_PPI mVariablePpi = {
  59   PeiGetVariable,
  60   PeiGetNextVariableName
  61 };
  62
  63 EFI_PEI_PPI_DESCRIPTOR     mPpiListVariable = {
  64   (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  65   &gEfiPeiReadOnlyVariablePpiGuid,
  66   &mVariablePpi
  67 };
  68
  69 EFI_PEI_PPI_DESCRIPTOR     mReadOnlyVariableThunkPresent = {
  70     (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  71     &gPeiReadonlyVariableThunkPresentPpiGuid,
  72     NULL
  73 };
  74
  75
  76 /**
  77   Standard entry point of a PEIM.
  78
  79   @param FfsHeadher  The FFS file header
  80   @param PeiServices  General purpose services available to every PEIM.
  81
  82   @retval EFI_SUCCESS If the gEfiPeiReadOnlyVariablePpiGuid interface could be successfully installed.
  83
  84 **/
  85 EFI_STATUS
  86 EFIAPI
  87 PeimInitializeReadOnlyVariable (
  88   IN EFI_PEI_FILE_HANDLE     FfsHeader,
  89   IN CONST EFI_PEI_SERVICES  **PeiServices
  90   )
  91 {
  92   VOID        *Interface;
  93   EFI_STATUS  Status;
  94
  95   //
  96   // Make sure ReadOnlyVariableToReadOnlyVariable2 module is not present. If so, the call chain will form a
  97   // infinite loop: ReadOnlyVariable -> ReadOnlyVariable2 -> ReadOnlyVariable -> ....
  98   //
  99   Status = PeiServicesLocatePpi (&gPeiReadonlyVariableThunkPresentPpiGuid, 0, NULL, &Interface);
 100   ASSERT (Status == EFI_NOT_FOUND);
 101
 102   Status = PeiServicesInstallPpi (&mReadOnlyVariableThunkPresent);
 103   ASSERT_EFI_ERROR (Status);
 104
 105   //
 106   // Publish the variable capability to other modules
 107   //
 108   return (*PeiServices)->InstallPpi (PeiServices, &mPpiListVariable);
 109 }
 110
 111 /**
 112   Provide the read variable functionality of the variable services.
 113
 114   @param  PeiServices           General purpose services available to every PEIM.
 115   @param  VariableName          The variable name
 116   @param  VendorGuid            The vendor's GUID
 117   @param  Attributes            Pointer to the attribute
 118   @param  DataSize              Size of data
 119   @param  Data                  Pointer to data
 120
 121   @retval EFI_SUCCESS           The interface could be successfully installed
 122   @retval EFI_NOT_FOUND         The variable could not be discovered
 123   @retval EFI_BUFFER_TOO_SMALL  The caller buffer is not large enough
 124
 125 **/
 126 EFI_STATUS
 127 EFIAPI
 128 PeiGetVariable (
 129   IN  EFI_PEI_SERVICES  **PeiServices,
 130   IN  CHAR16            *VariableName,
 131   IN  EFI_GUID          *VendorGuid,
 132   OUT UINT32            *Attributes OPTIONAL,
 133   IN  OUT UINTN         *DataSize,
 134   OUT VOID              *Data
 135   )
 136 {
 137   EFI_STATUS                      Status;
 138   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
 139
 140   Status = (*PeiServices)->LocatePpi (
 141                              (CONST EFI_PEI_SERVICES **)PeiServices,
 142                              &gEfiPeiReadOnlyVariable2PpiGuid,
 143                              0,
 144                              NULL,
 145                              (VOID **)&ReadOnlyVariable2
 146                              );
 147   ASSERT_EFI_ERROR (Status);
 148
 149   return ReadOnlyVariable2->GetVariable (
 150                               ReadOnlyVariable2,
 151                               VariableName,
 152                               VendorGuid,
 153                               Attributes,
 154                               DataSize,
 155                               Data
 156                               );
 157 }
 158
 159 /**
 160   Provide the get next variable functionality of the variable services.
 161
 162   @param  PeiServices           General purpose services available to every PEIM.
 163   @param  VariabvleNameSize     The variable name's size.
 164   @param  VariableName          A pointer to the variable's name.
 165   @param  VariableGuid          A pointer to the EFI_GUID structure.
 166   @param  VariableNameSize      Size of the variable name
 167   @param  VariableName          The variable name
 168   @param  VendorGuid            The vendor's GUID
 169
 170   @retval EFI_SUCCESS           The interface could be successfully installed
 171   @retval EFI_NOT_FOUND         The variable could not be discovered
 172
 173 **/
 174 EFI_STATUS
 175 EFIAPI
 176 PeiGetNextVariableName (
 177   IN EFI_PEI_SERVICES  **PeiServices,
 178   IN OUT UINTN         *VariableNameSize,
 179   IN OUT CHAR16        *VariableName,
 180   IN OUT EFI_GUID      *VendorGuid
 181   )
 182 {
 183   EFI_STATUS                      Status;
 184   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
 185
 186   Status = (*PeiServices)->LocatePpi (
 187                              (CONST EFI_PEI_SERVICES **)PeiServices,
 188                              &gEfiPeiReadOnlyVariable2PpiGuid,
 189                              0,
 190                              NULL,
 191                              (VOID **)&ReadOnlyVariable2
 192                              );
 193   ASSERT_EFI_ERROR (Status);
 194
 195   return ReadOnlyVariable2->NextVariableName (
 196                               ReadOnlyVariable2,
 197                               VariableNameSize,
 198                               VariableName,
 199                               VendorGuid
 200                               );
 201 }