audk/MdePkg/Library/BaseMemoryLibRepStr/CompareMemWrapper.c

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/** @file
CompareMem() implementation.
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: CompareMemWrapper.c
The following BaseMemoryLib instances share the same version of this file:
BaseMemoryLib
BaseMemoryLibMmx
BaseMemoryLibSse2
BaseMemoryLibRepStr
PeiMemoryLib
DxeMemoryLib
**/
//
// Include common header file for this module.
//
#include "CommonHeader.h"
#include "MemLibInternals.h"
/**
Compares the contents of two buffers.
This function compares Length bytes of SourceBuffer to Length bytes of DestinationBuffer.
If all Length bytes of the two buffers are identical, then 0 is returned. Otherwise, the
value returned is the first mismatched byte in SourceBuffer subtracted from the first
mismatched byte in DestinationBuffer.
If Length > 0 and DestinationBuffer is NULL and Length > 0, then ASSERT().
If Length > 0 and SourceBuffer is NULL and Length > 0, then ASSERT().
If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then ASSERT().
If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().
@param DestinationBuffer Pointer to the destination buffer to compare.
@param SourceBuffer Pointer to the source buffer to compare.
@param Length Number of bytes to compare.
@return 0 All Length bytes of the two buffers are identical.
@retval Non-zero The first mismatched byte in SourceBuffer subtracted from the first
mismatched byte in DestinationBuffer.
**/
INTN
EFIAPI
CompareMem (
IN CONST VOID *DestinationBuffer,
IN CONST VOID *SourceBuffer,
IN UINTN Length
)
{
if (Length == 0) {
return 0;
}
ASSERT (DestinationBuffer != NULL);
ASSERT (SourceBuffer != NULL);
ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)DestinationBuffer));
ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)SourceBuffer));
return InternalMemCompareMem (DestinationBuffer, SourceBuffer, Length);
}