EdkCompatibilityPkg/Compatibility/ReadOnlyVariableToReadOnlyVariable2Thunk/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 /**
  70   Standard entry point of a PEIM.
  71
  72   @param FfsHeadher  The FFS file header
  73   @param PeiServices  General purpose services available to every PEIM.
  74
  75   @retval EFI_SUCCESS If the gEfiPeiReadOnlyVariablePpiGuid interface could be successfully installed.
  76
  77 **/
  78 EFI_STATUS
  79 EFIAPI
  80 PeimInitializeReadOnlyVariable (
  81   IN EFI_PEI_FILE_HANDLE     FfsHeader,
  82   IN CONST EFI_PEI_SERVICES  **PeiServices
  83   )
  84 {
  85   VOID        *Interface;
  86   EFI_STATUS  Status;
  87
  88   //
  89   // Make sure ReadOnlyVariableToReadOnlyVariable2 module is not present. If so, the call chain will form a
  90   // infinite loop: ReadOnlyVariable -> ReadOnlyVariable2 -> ReadOnlyVariable -> ....
  91   //
  92   Status = PeiServicesLocatePpi (&gPeiReadonlyVariableThunkPresentPpiGuid, 0, NULL, &Interface);
  93   ASSERT (Status == EFI_NOT_FOUND);
  94
  95   //
  96   // Publish the variable capability to other modules
  97   //
  98   return (*PeiServices)->InstallPpi (PeiServices, &mPpiListVariable);
  99 }
 100
 101 /**
 102   Provide the read variable functionality of the variable services.
 103
 104   @param  PeiServices           General purpose services available to every PEIM.
 105   @param  VariableName          The variable name
 106   @param  VendorGuid            The vendor's GUID
 107   @param  Attributes            Pointer to the attribute
 108   @param  DataSize              Size of data
 109   @param  Data                  Pointer to data
 110
 111   @retval EFI_SUCCESS           The interface could be successfully installed
 112   @retval EFI_NOT_FOUND         The variable could not be discovered
 113   @retval EFI_BUFFER_TOO_SMALL  The caller buffer is not large enough
 114
 115 **/
 116 EFI_STATUS
 117 EFIAPI
 118 PeiGetVariable (
 119   IN  EFI_PEI_SERVICES  **PeiServices,
 120   IN  CHAR16            *VariableName,
 121   IN  EFI_GUID          *VendorGuid,
 122   OUT UINT32            *Attributes OPTIONAL,
 123   IN  OUT UINTN         *DataSize,
 124   OUT VOID              *Data
 125   )
 126 {
 127   EFI_STATUS                      Status;
 128   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
 129
 130   Status = (*PeiServices)->LocatePpi (
 131                              (CONST EFI_PEI_SERVICES **)PeiServices,
 132                              &gEfiPeiReadOnlyVariable2PpiGuid,
 133                              0,
 134                              NULL,
 135                              (VOID **)&ReadOnlyVariable2
 136                              );
 137   ASSERT_EFI_ERROR (Status);
 138
 139   return ReadOnlyVariable2->GetVariable (
 140                               ReadOnlyVariable2,
 141                               VariableName,
 142                               VendorGuid,
 143                               Attributes,
 144                               DataSize,
 145                               Data
 146                               );
 147 }
 148
 149 /**
 150   Provide the get next variable functionality of the variable services.
 151
 152   @param  PeiServices           General purpose services available to every PEIM.
 153   @param  VariabvleNameSize     The variable name's size.
 154   @param  VariableName          A pointer to the variable's name.
 155   @param  VariableGuid          A pointer to the EFI_GUID structure.
 156   @param  VariableNameSize      Size of the variable name
 157   @param  VariableName          The variable name
 158   @param  VendorGuid            The vendor's GUID
 159
 160   @retval EFI_SUCCESS           The interface could be successfully installed
 161   @retval EFI_NOT_FOUND         The variable could not be discovered
 162
 163 **/
 164 EFI_STATUS
 165 EFIAPI
 166 PeiGetNextVariableName (
 167   IN EFI_PEI_SERVICES  **PeiServices,
 168   IN OUT UINTN         *VariableNameSize,
 169   IN OUT CHAR16        *VariableName,
 170   IN OUT EFI_GUID      *VendorGuid
 171   )
 172 {
 173   EFI_STATUS                      Status;
 174   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
 175
 176   Status = (*PeiServices)->LocatePpi (
 177                              (CONST EFI_PEI_SERVICES **)PeiServices,
 178                              &gEfiPeiReadOnlyVariable2PpiGuid,
 179                              0,
 180                              NULL,
 181                              (VOID **)&ReadOnlyVariable2
 182                              );
 183   ASSERT_EFI_ERROR (Status);
 184
 185   return ReadOnlyVariable2->NextVariableName (
 186                               ReadOnlyVariable2,
 187                               VariableNameSize,
 188                               VariableName,
 189                               VendorGuid
 190                               );
 191 }