X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=MdePkg%2FLibrary%2FPeiMemoryLib%2FMemLibGuid.c;h=4cc95d3aab563392e6901f2ee5bf24d8cb5aadfd;hp=36da5b742424ea92fbe05836e41d9b6587ebac1c;hb=9095d37b8fe5bfc3d02adad6ba7fd7359ebc0107;hpb=582510249f2fb1334e507b99421b9485f6b89159

diff --git a/MdePkg/Library/PeiMemoryLib/MemLibGuid.c b/MdePkg/Library/PeiMemoryLib/MemLibGuid.c
index 36da5b7424..4cc95d3aab 100644
--- a/MdePkg/Library/PeiMemoryLib/MemLibGuid.c
+++ b/MdePkg/Library/PeiMemoryLib/MemLibGuid.c
@@ -1,38 +1,41 @@
 /** @file
   Implementation of GUID functions.
 
-  Copyright (c) 2006, Intel Corporation<BR>
-  All rights reserved. This program and the accompanying materials
-  are licensed and made available under the terms and conditions of the BSD License
-  which accompanies this distribution.  The full text of the license may be found at
-  http://opensource.org/licenses/bsd-license.php
-
-  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
-  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
-
-  Module Name:  MemLibGuid.c
-
-  The following BaseMemoryLib instances share the same version of this file:
+  The following BaseMemoryLib instances contain the same copy of this file:
 
     BaseMemoryLib
     BaseMemoryLibMmx
     BaseMemoryLibSse2
     BaseMemoryLibRepStr
+    BaseMemoryLibOptDxe
+    BaseMemoryLibOptPei
     PeiMemoryLib
-    DxeMemoryLib
+    UefiMemoryLib
+
+  Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php.
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 
 **/
 
+#include "MemLibInternals.h"
+
 /**
   Copies a source GUID to a destination GUID.
 
   This function copies the contents of the 128-bit GUID specified by SourceGuid to
   DestinationGuid, and returns DestinationGuid.
+
   If DestinationGuid is NULL, then ASSERT().
   If SourceGuid is NULL, then ASSERT().
 
-  @param  DestinationGuid   Pointer to the destination GUID.
-  @param  SourceGuid        Pointer to the source GUID.
+  @param  DestinationGuid   The pointer to the destination GUID.
+  @param  SourceGuid        The pointer to the source GUID.
 
   @return DestinationGuid.
 
@@ -60,6 +63,7 @@ CopyGuid (
 
   This function compares Guid1 to Guid2.  If the GUIDs are identical then TRUE is returned.
   If there are any bit differences in the two GUIDs, then FALSE is returned.
+
   If Guid1 is NULL, then ASSERT().
   If Guid2 is NULL, then ASSERT().
 
@@ -94,19 +98,20 @@ CompareGuid (
   Scans a target buffer for a GUID, and returns a pointer to the matching GUID
   in the target buffer.
 
-  This function searches target the buffer specified by Buffer and Length from
+  This function searches the target buffer specified by Buffer and Length from
   the lowest address to the highest address at 128-bit increments for the 128-bit
   GUID value that matches Guid.  If a match is found, then a pointer to the matching
   GUID in the target buffer is returned.  If no match is found, then NULL is returned.
   If Length is 0, then NULL is returned.
+
   If Length > 0 and Buffer is NULL, then ASSERT().
   If Buffer is not aligned on a 32-bit boundary, then ASSERT().
   If Length is not aligned on a 128-bit boundary, then ASSERT().
-  If Length is greater than (MAX_ADDRESS ? Buffer + 1), then ASSERT(). 
+  If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
 
-  @param  Buffer  Pointer to the target buffer to scan.
-  @param  Length  Number of bytes in Buffer to scan.
-  @param  Guid    Value to search for in the target buffer.
+  @param  Buffer  The pointer to the target buffer to scan.
+  @param  Length  The number of bytes in Buffer to scan.
+  @param  Guid    The value to search for in the target buffer.
 
   @return A pointer to the matching Guid in the target buffer or NULL otherwise.
 
@@ -135,3 +140,32 @@ ScanGuid (
   }
   return NULL;
 }
+
+/**
+  Checks if the given GUID is a zero GUID.
+
+  This function checks whether the given GUID is a zero GUID. If the GUID is
+  identical to a zero GUID then TRUE is returned. Otherwise, FALSE is returned.
+
+  If Guid is NULL, then ASSERT().
+
+  @param  Guid        The pointer to a 128 bit GUID.
+
+  @retval TRUE        Guid is a zero GUID.
+  @retval FALSE       Guid is not a zero GUID.
+
+**/
+BOOLEAN
+EFIAPI
+IsZeroGuid (
+  IN CONST GUID  *Guid
+  )
+{
+  UINT64  LowPartOfGuid;
+  UINT64  HighPartOfGuid;
+
+  LowPartOfGuid  = ReadUnaligned64 ((CONST UINT64*) Guid);
+  HighPartOfGuid = ReadUnaligned64 ((CONST UINT64*) Guid + 1);
+
+  return (BOOLEAN) (LowPartOfGuid == 0 && HighPartOfGuid == 0);
+}