/** @file\r
CompareMem() implementation.\r
\r
- Copyright (c) 2006, Intel Corporation<BR>\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
-\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
- Module Name: CompareMemWrapper.c\r
-\r
- The following BaseMemoryLib instances share the same version of this file:\r
-\r
+ The following BaseMemoryLib instances contain the same copy of this file:\r
BaseMemoryLib\r
BaseMemoryLibMmx\r
BaseMemoryLibSse2\r
BaseMemoryLibRepStr\r
+ BaseMemoryLibOptDxe\r
+ BaseMemoryLibOptPei\r
PeiMemoryLib\r
UefiMemoryLib\r
\r
+Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
+SPDX-License-Identifier: BSD-2-Clause-Patent\r
+\r
**/\r
\r
#include "MemLibInternals.h"\r
\r
/**\r
- Compares two memory buffers of a given length.\r
+ Compares the contents of two buffers.\r
\r
- This function compares Length bytes of SourceBuffer to Length bytes of\r
- DestinationBuffer. If all Length bytes of the two buffers are identical, then\r
- 0 is returned. Otherwise, the value returned is the first mismatched byte in\r
- SourceBuffer subtracted from the first mismatched byte in DestinationBuffer.\r
+ This function compares Length bytes of SourceBuffer to Length bytes of DestinationBuffer.\r
+ If all Length bytes of the two buffers are identical, then 0 is returned. Otherwise, the\r
+ value returned is the first mismatched byte in SourceBuffer subtracted from the first\r
+ mismatched byte in DestinationBuffer.\r
\r
- If DestinationBuffer is NULL and Length > 0, then ASSERT().\r
- If SourceBuffer is NULL and Length > 0, then ASSERT().\r
- If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then\r
- ASSERT().\r
+ If Length > 0 and DestinationBuffer is NULL, then ASSERT().\r
+ If Length > 0 and SourceBuffer is NULL, then ASSERT().\r
+ If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then ASSERT().\r
If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().\r
\r
- @param DestinationBuffer First memory buffer\r
- @param SourceBuffer Second memory buffer\r
- @param Length Length of DestinationBuffer and SourceBuffer memory\r
- regions to compare\r
+ @param DestinationBuffer The pointer to the destination buffer to compare.\r
+ @param SourceBuffer The pointer to the source buffer to compare.\r
+ @param Length The number of bytes to compare.\r
\r
- @retval 0 if DestinationBuffer == SourceBuffer\r
- @retval Non-zero if DestinationBuffer != SourceBuffer\r
+ @return 0 All Length bytes of the two buffers are identical.\r
+ @retval Non-zero The first mismatched byte in SourceBuffer subtracted from the first\r
+ mismatched byte in DestinationBuffer.\r
\r
**/\r
INTN\r
EFIAPI\r
CompareMem (\r
- IN CONST VOID *DestinationBuffer,\r
- IN CONST VOID *SourceBuffer,\r
- IN UINTN Length\r
+ IN CONST VOID *DestinationBuffer,\r
+ IN CONST VOID *SourceBuffer,\r
+ IN UINTN Length\r
)\r
{\r
- ASSERT (DestinationBuffer != NULL);\r
- ASSERT (SourceBuffer != NULL);\r
- ASSERT (Length <= MAX_ADDRESS - (UINTN)DestinationBuffer + 1);\r
- ASSERT (Length <= MAX_ADDRESS - (UINTN)SourceBuffer + 1);\r
- if (Length == 0) {\r
+ if (Length == 0 || DestinationBuffer == SourceBuffer) {\r
return 0;\r
}\r
+ ASSERT (DestinationBuffer != NULL);\r
+ ASSERT (SourceBuffer != NULL);\r
+ ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)DestinationBuffer));\r
+ ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)SourceBuffer));\r
+\r
return InternalMemCompareMem (DestinationBuffer, SourceBuffer, Length);\r
}\r