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 //
  34 // Functions
  35 //
  36 /**
  37   Provide the functionality of the variable services.
  38
  39   @param  FileHandle  Handle of the file being invoked.
  40                       Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
  41   @param  PeiServices  General purpose services available to every PEIM.
  42
  43   @retval EFI_SUCCESS  If the interface could be successfully installed
  44   @retval Others       Returned from PeiServicesInstallPpi()
  45
  46 **/
  47 EFI_STATUS
  48 EFIAPI
  49 PeimInitializeVariableServices (
  50   IN       EFI_PEI_FILE_HANDLE       FileHandle,
  51   IN CONST EFI_PEI_SERVICES          **PeiServices
  52   );
  53
  54 /**
  55   This service retrieves a variable's value using its name and GUID.
  56
  57   Read the specified variable from the UEFI variable store. If the Data
  58   buffer is too small to hold the contents of the variable, the error
  59   EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
  60   size to obtain the data.
  61
  62   @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  63   @param  VariableName          A pointer to a null-terminated string that is the variable's name.
  64   @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
  65                                 VariableGuid and VariableName must be unique.
  66   @param  Attributes            If non-NULL, on return, points to the variable's attributes.
  67   @param  DataSize              On entry, points to the size in bytes of the Data buffer.
  68                                 On return, points to the size of the data returned in Data.
  69   @param  Data                  Points to the buffer which will hold the returned variable value.
  70
  71   @retval EFI_SUCCESS           The variable was read successfully.
  72   @retval EFI_NOT_FOUND         The variable could not be found.
  73   @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
  74                                 DataSize is updated with the size required for
  75                                 the specified variable.
  76   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
  77   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
  78
  79 **/
  80 EFI_STATUS
  81 EFIAPI
  82 PeiGetVariable (
  83   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
  84   IN CONST  CHAR16                          *VariableName,
  85   IN CONST  EFI_GUID                        *VariableGuid,
  86   OUT       UINT32                          *Attributes,
  87   IN OUT    UINTN                           *DataSize,
  88   OUT       VOID                            *Data
  89   );
  90
  91 /**
  92   Return the next variable name and GUID.
  93
  94   This function is called multiple times to retrieve the VariableName
  95   and VariableGuid of all variables currently available in the system.
  96   On each call, the previous results are passed into the interface,
  97   and, on return, the interface returns the data for the next
  98   interface. When the entire variable list has been returned,
  99   EFI_NOT_FOUND is returned.
 100
 101   @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
 102
 103   @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
 104   @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
 105                             On return, points to the next variable's null-terminated name string.
 106
 107   @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the variable's GUID.
 108                             On return, a pointer to the next variable's GUID.
 109
 110   @retval EFI_SUCCESS           The variable was read successfully.
 111   @retval EFI_NOT_FOUND         The variable could not be found.
 112   @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
 113                                 data. VariableNameSize is updated with the size
 114                                 required for the specified variable.
 115   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
 116                                 VariableNameSize is NULL.
 117   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
 118
 119 **/
 120 EFI_STATUS
 121 EFIAPI
 122 PeiGetNextVariableName (
 123   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 124   IN OUT UINTN                              *VariableNameSize,
 125   IN OUT CHAR16                             *VariableName,
 126   IN OUT EFI_GUID                           *VariableGuid
 127   );
 128
 129 #endif