MdePkg: Minor update to the Data parameter for PEI GetVariable()

[mirror_edk2.git] / MdePkg / Include / Ppi / ReadOnlyVariable2.h

diff --git a/MdePkg/Include/Ppi/ReadOnlyVariable2.h b/MdePkg/Include/Ppi/ReadOnlyVariable2.h
index 23de911989b8aa712b892d8234500bb0e652d02f..6d8ea603811fbdf810915f0505ee7eff0e8991ee 100644 (file)
--- a/MdePkg/Include/Ppi/ReadOnlyVariable2.h
+++ b/MdePkg/Include/Ppi/ReadOnlyVariable2.h
@@ -2,14 +2,14 @@
   This file declares Read-only Variable Service2 PPI.\r
   This ppi permits read-only access to the UEFI variable store during the PEI phase.\r
 \r
-  Copyright (c) 2006 - 2009, Intel Corporation                                                         \r
-  All rights reserved. This program and the accompanying materials                          \r
-  are licensed and made available under the terms and conditions of the BSD License         \r
-  which accompanies this distribution.  The full text of the license may be found at        \r
-  http://opensource.org/licenses/bsd-license.php                                            \r
+Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>\r
+This program and the accompanying materials are licensed and made available under \r
+the terms and conditions of the BSD License that accompanies this distribution.  \r
+The full text of the license may be found at\r
+http://opensource.org/licenses/bsd-license.php.                                             \r
 \r
-  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
-  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
 \r
   @par Revision Reference:\r
   This PPI is introduced in PI Version 1.0.\r
@@ -35,15 +35,16 @@ typedef struct _EFI_PEI_READ_ONLY_VARIABLE2_PPI  EFI_PEI_READ_ONLY_VARIABLE2_PPI
 \r
   @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.\r
   @param  VariableName          A pointer to a null-terminated string that is the variable's name.\r
-  @param  VendorGuid            A pointer to an EFI_GUID that is the variable's GUID. The combination of\r
+  @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of\r
                                 VariableGuid and VariableName must be unique.\r
   @param  Attributes            If non-NULL, on return, points to the variable's attributes.\r
   @param  DataSize              On entry, points to the size in bytes of the Data buffer.\r
                                 On return, points to the size of the data returned in Data.\r
   @param  Data                  Points to the buffer which will hold the returned variable value.\r
+                                May be NULL with a zero DataSize in order to determine the size of the buffer needed.\r
 \r
   @retval EFI_SUCCESS           The variable was read successfully.\r
-  @retval EFI_NOT_FOUND         The variable could not be found.\r
+  @retval EFI_NOT_FOUND         The variable was not found.\r
   @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data. \r
                                 DataSize is updated with the size required for \r
                                 the specified variable.\r
@@ -59,7 +60,7 @@ EFI_STATUS
   IN CONST  EFI_GUID                        *VariableGuid,\r
   OUT       UINT32                          *Attributes,\r
   IN OUT    UINTN                           *DataSize,\r
-  OUT       VOID                            *Data\r
+  OUT       VOID                            *Data OPTIONAL\r
   );\r
 \r
 \r
@@ -76,10 +77,11 @@ EFI_STATUS
   @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.\r
 \r
   @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.\r
+                            On return, the size of the variable name buffer.\r
   @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.\r
                             On return, points to the next variable's null-terminated name string.\r
 \r
-  @param  VendorGuid        On entry, a pointer to an EFI_GUID that is the variable's GUID. \r
+  @param  VariableGuid      On entry, a pointer to an EFI_GUID that is the variable's GUID. \r
                             On return, a pointer to the next variable's GUID.\r
 \r
   @retval EFI_SUCCESS           The variable was read successfully.\r