| 1 | /** @file
|
|---|
| 2 | CompareMem() implementation.
|
|---|
| 3 |
|
|---|
| 4 | The following BaseMemoryLib instances contain the same copy of this file:
|
|---|
| 5 | BaseMemoryLib
|
|---|
| 6 | BaseMemoryLibMmx
|
|---|
| 7 | BaseMemoryLibSse2
|
|---|
| 8 | BaseMemoryLibRepStr
|
|---|
| 9 | BaseMemoryLibOptDxe
|
|---|
| 10 | BaseMemoryLibOptPei
|
|---|
| 11 | PeiMemoryLib
|
|---|
| 12 | UefiMemoryLib
|
|---|
| 13 |
|
|---|
| 14 | Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
|
|---|
| 15 | SPDX-License-Identifier: BSD-2-Clause-Patent
|
|---|
| 16 |
|
|---|
| 17 | **/
|
|---|
| 18 |
|
|---|
| 19 | #include "MemLibInternals.h"
|
|---|
| 20 |
|
|---|
| 21 | /**
|
|---|
| 22 | Compares the contents of two buffers.
|
|---|
| 23 |
|
|---|
| 24 | This function compares Length bytes of SourceBuffer to Length bytes of DestinationBuffer.
|
|---|
| 25 | If all Length bytes of the two buffers are identical, then 0 is returned. Otherwise, the
|
|---|
| 26 | value returned is the first mismatched byte in SourceBuffer subtracted from the first
|
|---|
| 27 | mismatched byte in DestinationBuffer.
|
|---|
| 28 |
|
|---|
| 29 | If Length > 0 and DestinationBuffer is NULL, then ASSERT().
|
|---|
| 30 | If Length > 0 and SourceBuffer is NULL, then ASSERT().
|
|---|
| 31 | If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then ASSERT().
|
|---|
| 32 | If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().
|
|---|
| 33 |
|
|---|
| 34 | @param DestinationBuffer The pointer to the destination buffer to compare.
|
|---|
| 35 | @param SourceBuffer The pointer to the source buffer to compare.
|
|---|
| 36 | @param Length The number of bytes to compare.
|
|---|
| 37 |
|
|---|
| 38 | @return 0 All Length bytes of the two buffers are identical.
|
|---|
| 39 | @retval Non-zero The first mismatched byte in SourceBuffer subtracted from the first
|
|---|
| 40 | mismatched byte in DestinationBuffer.
|
|---|
| 41 |
|
|---|
| 42 | **/
|
|---|
| 43 | INTN
|
|---|
| 44 | EFIAPI
|
|---|
| 45 | CompareMem (
|
|---|
| 46 | IN CONST VOID *DestinationBuffer,
|
|---|
| 47 | IN CONST VOID *SourceBuffer,
|
|---|
| 48 | IN UINTN Length
|
|---|
| 49 | )
|
|---|
| 50 | {
|
|---|
| 51 | if ((Length == 0) || (DestinationBuffer == SourceBuffer)) {
|
|---|
| 52 | return 0;
|
|---|
| 53 | }
|
|---|
| 54 |
|
|---|
| 55 | ASSERT (DestinationBuffer != NULL);
|
|---|
| 56 | ASSERT (SourceBuffer != NULL);
|
|---|
| 57 | ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)DestinationBuffer));
|
|---|
| 58 | ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)SourceBuffer));
|
|---|
| 59 |
|
|---|
| 60 | return InternalMemCompareMem (DestinationBuffer, SourceBuffer, Length);
|
|---|
| 61 | }
|
|---|
