MdePkg/Library/BaseLib/SwapBytes32.c

   1 /** @file
   2   Math worker functions.
   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 **/
  14
  15 //
  16 // Include common header file for this module.
  17 //
  18
  19
  20 #include "BaseLibInternals.h"
  21
  22 /**
  23   Switches the endianess of a 32-bit integer.
  24
  25   This function swaps the bytes in a 32-bit unsigned value to switch the value
  26   from little endian to big endian or vice versa. The byte swapped value is
  27   returned.
  28
  29   @param  Operand A 32-bit unsigned value.
  30
  31   @return The byte swaped Operand.
  32
  33 **/
  34 UINT32
  35 EFIAPI
  36 SwapBytes32 (
  37   IN      UINT32                    Operand
  38   )
  39 {
  40   UINT32  LowerBytes;
  41   UINT32  HigherBytes;
  42
  43   LowerBytes  = (UINT32) SwapBytes16 ((UINT16) Operand);
  44   HigherBytes = (UINT32) SwapBytes16 ((UINT16) (Operand >> 16));
  45
  46   return (LowerBytes << 16 | HigherBytes);
  47 }