MdeModulePkg/Universal/Variable/Pei/Variable.h

   1 /** @file
   2
   3   The internal header file includes the common header files, defines
   4   internal structure and functions used by PeiVariable module.
   5
   6 Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
   7 This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #ifndef _PEI_VARIABLE_H_
  18 #define _PEI_VARIABLE_H_
  19
  20 #include <PiPei.h>
  21 #include <Ppi/ReadOnlyVariable2.h>
  22
  23 #include <Library/DebugLib.h>
  24 #include <Library/PeimEntryPoint.h>
  25 #include <Library/HobLib.h>
  26 #include <Library/PcdLib.h>
  27 #include <Library/BaseMemoryLib.h>
  28 #include <Library/PeiServicesTablePointerLib.h>
  29 #include <Library/PeiServicesLib.h>
  30
  31 #include <Guid/VariableFormat.h>
  32 #include <Guid/VariableIndexTable.h>
  33 #include <Guid/SystemNvDataGuid.h>
  34
  35 typedef enum {
  36   VariableStoreTypeHob,
  37   VariableStoreTypeNv,
  38   VariableStoreTypeMax
  39 } VARIABLE_STORE_TYPE;
  40
  41 //
  42 // Functions
  43 //
  44 /**
  45   Provide the functionality of the variable services.
  46
  47   @param  FileHandle  Handle of the file being invoked.
  48                       Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
  49   @param  PeiServices  General purpose services available to every PEIM.
  50
  51   @retval EFI_SUCCESS  If the interface could be successfully installed
  52   @retval Others       Returned from PeiServicesInstallPpi()
  53
  54 **/
  55 EFI_STATUS
  56 EFIAPI
  57 PeimInitializeVariableServices (
  58   IN       EFI_PEI_FILE_HANDLE       FileHandle,
  59   IN CONST EFI_PEI_SERVICES          **PeiServices
  60   );
  61
  62 /**
  63   This service retrieves a variable's value using its name and GUID.
  64
  65   Read the specified variable from the UEFI variable store. If the Data
  66   buffer is too small to hold the contents of the variable, the error
  67   EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
  68   size to obtain the data.
  69
  70   @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  71   @param  VariableName          A pointer to a null-terminated string that is the variable's name.
  72   @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
  73                                 VariableGuid and VariableName must be unique.
  74   @param  Attributes            If non-NULL, on return, points to the variable's attributes.
  75   @param  DataSize              On entry, points to the size in bytes of the Data buffer.
  76                                 On return, points to the size of the data returned in Data.
  77   @param  Data                  Points to the buffer which will hold the returned variable value.
  78
  79   @retval EFI_SUCCESS           The variable was read successfully.
  80   @retval EFI_NOT_FOUND         The variable could not be found.
  81   @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
  82                                 DataSize is updated with the size required for
  83                                 the specified variable.
  84   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
  85   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
  86
  87 **/
  88 EFI_STATUS
  89 EFIAPI
  90 PeiGetVariable (
  91   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
  92   IN CONST  CHAR16                          *VariableName,
  93   IN CONST  EFI_GUID                        *VariableGuid,
  94   OUT       UINT32                          *Attributes,
  95   IN OUT    UINTN                           *DataSize,
  96   OUT       VOID                            *Data
  97   );
  98
  99 /**
 100   Return the next variable name and GUID.
 101
 102   This function is called multiple times to retrieve the VariableName
 103   and VariableGuid of all variables currently available in the system.
 104   On each call, the previous results are passed into the interface,
 105   and, on return, the interface returns the data for the next
 106   interface. When the entire variable list has been returned,
 107   EFI_NOT_FOUND is returned.
 108
 109   @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
 110
 111   @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
 112   @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
 113                             On return, points to the next variable's null-terminated name string.
 114
 115   @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the variable's GUID.
 116                             On return, a pointer to the next variable's GUID.
 117
 118   @retval EFI_SUCCESS           The variable was read successfully.
 119   @retval EFI_NOT_FOUND         The variable could not be found.
 120   @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
 121                                 data. VariableNameSize is updated with the size
 122                                 required for the specified variable.
 123   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
 124                                 VariableNameSize is NULL.
 125   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
 126
 127 **/
 128 EFI_STATUS
 129 EFIAPI
 130 PeiGetNextVariableName (
 131   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 132   IN OUT UINTN                              *VariableNameSize,
 133   IN OUT CHAR16                             *VariableName,
 134   IN OUT EFI_GUID                           *VariableGuid
 135   );
 136
 137 #endif