161 lines
2.2 KiB
NASM
161 lines
2.2 KiB
NASM
title "Byte Swap Functions"
|
|
|
|
|
|
; Copyright (c) 1997 Microsoft Corporation
|
|
|
|
; Module Name:
|
|
|
|
; movemem.asm
|
|
|
|
; Abstract:
|
|
|
|
; This module implements functions to perform byte swapping operations.
|
|
|
|
|
|
; Author:
|
|
|
|
; Forrest Foltz (forrestf) 12-Dec-1997
|
|
|
|
; Environment:
|
|
|
|
; User or Kernel mode.
|
|
|
|
; Revision History:
|
|
|
|
|
|
.486p
|
|
.xlist
|
|
include ks386.inc
|
|
include callconv.inc ; calling convention macros
|
|
.list
|
|
|
|
|
|
; Alignment for functions in this module
|
|
|
|
|
|
CODE_ALIGNMENT macro
|
|
align 16
|
|
endm
|
|
|
|
|
|
_TEXT$00 SEGMENT PARA PUBLIC 'CODE'
|
|
ASSUME DS:FLAT, ES:FLAT, SS:NOTHING, FS:NOTHING, GS:NOTHING
|
|
|
|
PAGE
|
|
SUBTTL "RtlUshortByteSwap"
|
|
|
|
|
|
; USHORT
|
|
; RtlUshortByteSwap(
|
|
; IN USHORT Source
|
|
; )
|
|
|
|
; /*++
|
|
|
|
; Routine Description:
|
|
|
|
; The RtlfUshortByteSwap function exchanges bytes 0 and 1 of Source
|
|
; and returns the resulting USHORT.
|
|
|
|
; Arguments:
|
|
|
|
; (cx) Source - 16-bit value to byteswap.
|
|
|
|
; Return Value:
|
|
|
|
; Swapped 16-bit value.
|
|
|
|
|
|
|
|
CODE_ALIGNMENT
|
|
|
|
cPublicFastCall RtlUshortByteSwap ,1
|
|
cPublicFpo 0, 0
|
|
|
|
mov ah, cl
|
|
mov al, ch
|
|
fstRET RtlUshortByteSwap
|
|
|
|
fstENDP RtlUshortByteSwap
|
|
|
|
|
|
PAGE
|
|
SUBTTL "RtlUlongByteSwap"
|
|
|
|
|
|
; ULONG
|
|
; RtlUlongByteSwap(
|
|
; IN ULONG Source
|
|
; )
|
|
|
|
; /*++
|
|
|
|
; Routine Description:
|
|
|
|
; The RtlUlongByteSwap function exchanges byte pairs 0:3 and 1:2 of
|
|
; Source and returns the the resulting ULONG.
|
|
|
|
; Arguments:
|
|
|
|
; (ecx) Source - 32-bit value to byteswap.
|
|
|
|
; Return Value:
|
|
|
|
; Swapped 32-bit value.
|
|
|
|
|
|
|
|
CODE_ALIGNMENT
|
|
|
|
cPublicFastCall RtlUlongByteSwap ,1
|
|
cPublicFpo 0, 0
|
|
|
|
mov eax, ecx
|
|
bswap eax
|
|
fstRET RtlUlongByteSwap
|
|
|
|
fstENDP RtlUlongByteSwap
|
|
|
|
|
|
PAGE
|
|
SUBTTL "RtlUlonglongByteSwap"
|
|
|
|
|
|
; ULONG
|
|
; RtlUlonglongByteSwap(
|
|
; IN ULONGLONG Source
|
|
; )
|
|
|
|
; /*++
|
|
|
|
; Routine Description:
|
|
|
|
; The RtlUlonglongByteSwap function exchanges byte pairs 0:7, 1:6, 2:5,
|
|
; and 3:4 of Source and returns the resulting ULONGLONG.
|
|
|
|
; Arguments:
|
|
|
|
; (edx:ecx) Source - 64-bit value to byteswap.
|
|
|
|
; Return Value:
|
|
|
|
; Swapped 64-bit value.
|
|
|
|
|
|
|
|
CODE_ALIGNMENT
|
|
|
|
cPublicFastCall RtlUlonglongByteSwap ,1
|
|
cPublicFpo 0, 0
|
|
|
|
mov edx, eax
|
|
mov eax, ecx
|
|
bswap edx
|
|
bswap eax
|
|
fstRET RtlUlonglongByteSwap
|
|
|
|
fstENDP RtlUlonglongByteSwap
|
|
|
|
_TEXT$00 ends
|
|
end
|