MdePkg/Library/BaseMemoryLibMmx/CopyMemWrapper.c

   1 /** @file
   2   CopyMem() implementation.
   3
   4   Copyright (c) 2006, Intel Corporation<BR>
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13   Module Name:  CopyMemWrapper.c
  14
  15   The following BaseMemoryLib instances share the same version of this file:
  16
  17     BaseMemoryLib
  18     BaseMemoryLibMmx
  19     BaseMemoryLibSse2
  20     BaseMemoryLibRepStr
  21     PeiMemoryLib
  22     UefiMemoryLib
  23
  24 **/
  25
  26 #include "MemLibInternals.h"
  27
  28 /**
  29   Copy Length bytes from Source to Destination.
  30
  31   This function copies Length bytes from SourceBuffer to DestinationBuffer, and
  32   returns DestinationBuffer. The implementation must be reentrant, and it must
  33   handle the case where SourceBuffer overlaps DestinationBuffer.
  34
  35   If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then
  36   ASSERT().
  37   If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().
  38
  39   @param  Destination Target of copy
  40   @param  Source Place to copy from
  41   @param  Length Number of bytes to copy
  42
  43   @return Destination
  44
  45 **/
  46 VOID *
  47 EFIAPI
  48 CopyMem (
  49   OUT     VOID                      *Destination,
  50   IN      CONST VOID                *Source,
  51   IN      UINTN                     Length
  52   )
  53 {
  54   ASSERT (
  55     Destination == NULL ||
  56     Length <= MAX_ADDRESS - (UINTN)Destination + 1
  57     );
  58   ASSERT (
  59     Source == NULL ||
  60     Length <= MAX_ADDRESS - (UINTN)Source + 1
  61     );
  62   if (Destination == Source || Length == 0) {
  63     return Destination;
  64   }
  65   return InternalMemCopyMem (Destination, Source, Length);
  66 }