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/** @file
Implementation of GUID functions.
The following BaseMemoryLib instances contain the same copy of this file:
BaseMemoryLib
BaseMemoryLibMmx
BaseMemoryLibSse2
BaseMemoryLibRepStr
BaseMemoryLibOptDxe
BaseMemoryLibOptPei
PeiMemoryLib
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 The pointer to the destination GUID.
@param SourceGuid The pointer to the source GUID.
@return DestinationGuid.
**/
GUID *
EFIAPI
CopyGuid (
OUT GUID *DestinationGuid,
IN CONST GUID *SourceGuid
)
{
WriteUnaligned64 (
(UINT64*)DestinationGuid,
ReadUnaligned64 ((CONST UINT64*)SourceGuid)
);
WriteUnaligned64 (
(UINT64*)DestinationGuid + 1,
ReadUnaligned64 ((CONST UINT64*)SourceGuid + 1)
);
return DestinationGuid;
}
/**
Compares two GUIDs.
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().
@param Guid1 A pointer to a 128 bit GUID.
@param Guid2 A pointer to a 128 bit GUID.
@retval TRUE Guid1 and Guid2 are identical.
@retval FALSE Guid1 and Guid2 are not identical.
**/
BOOLEAN
EFIAPI
CompareGuid (
IN CONST GUID *Guid1,
IN CONST GUID *Guid2
)
{
UINT64 LowPartOfGuid1;
UINT64 LowPartOfGuid2;
UINT64 HighPartOfGuid1;
UINT64 HighPartOfGuid2;
LowPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1);
LowPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2);
HighPartOfGuid1 = ReadUnaligned64 ((CONST UINT64*) Guid1 + 1);
HighPartOfGuid2 = ReadUnaligned64 ((CONST UINT64*) Guid2 + 1);
return (BOOLEAN) (LowPartOfGuid1 == LowPartOfGuid2 && HighPartOfGuid1 == HighPartOfGuid2);
}
/**
Scans a target buffer for a GUID, and returns a pointer to the matching GUID
in the target buffer.
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().
@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.
**/
VOID *
EFIAPI
ScanGuid (
IN CONST VOID *Buffer,
IN UINTN Length,
IN CONST GUID *Guid
)
{
CONST GUID *GuidPtr;
ASSERT (((UINTN)Buffer & (sizeof (Guid->Data1) - 1)) == 0);
ASSERT (Length <= (MAX_ADDRESS - (UINTN)Buffer + 1));
ASSERT ((Length & (sizeof (*GuidPtr) - 1)) == 0);
GuidPtr = (GUID*)Buffer;
Buffer = GuidPtr + Length / sizeof (*GuidPtr);
while (GuidPtr < (CONST GUID*)Buffer) {
if (CompareGuid (GuidPtr, Guid)) {
return (VOID*)GuidPtr;
}
GuidPtr++;
}
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);
}