audk/MdePkg/Library/BaseMemoryLibOptDxe/CopyMemWrapper.c

60 lines
1.7 KiB
C

/** @file
CopyMem() implementation.
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>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "MemLibInternals.h"
/**
Copies a source buffer to a destination buffer, and returns the destination buffer.
This function copies Length bytes from SourceBuffer to DestinationBuffer, and returns
DestinationBuffer. The implementation must be reentrant, and it must handle the case
where SourceBuffer overlaps DestinationBuffer.
If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then ASSERT().
If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().
@param DestinationBuffer The pointer to the destination buffer of the memory copy.
@param SourceBuffer The pointer to the source buffer of the memory copy.
@param Length The number of bytes to copy from SourceBuffer to DestinationBuffer.
@return DestinationBuffer.
**/
VOID *
EFIAPI
CopyMem (
OUT VOID *DestinationBuffer,
IN CONST VOID *SourceBuffer,
IN UINTN Length
)
{
if (Length == 0) {
return DestinationBuffer;
}
ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)DestinationBuffer));
ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)SourceBuffer));
if (DestinationBuffer == SourceBuffer) {
return DestinationBuffer;
}
return InternalMemCopyMem (DestinationBuffer, SourceBuffer, Length);
}