汇编试验9

上海电力学院 实验报告 课程名称 汇编语言 实验项目 试验9 磁盘文件存储技术 姓名 李鑫 学号 20103277 班级 2010251 专业 计算机科学与技术 教师姓名 王 勇 实验日期 2012-5-7 一、 试验内容 参照试验指导书，和教材409页和414页程序，建立一个文件，并加密，mykey=6A（你姓第一个字母的 ASCII）例如，ASCII（j）=6A； 文件内容为 学号：20073487 姓名：jiangjinyu 班级： ****** 兴趣爱好： ******** 0 最后输入0，会避免显示出现异常 二、 程序源代码 1．建立文件 .model small .stack .data myname db 'lixin',0dh,0ah mystuNO db '20103277',0dh,0ah proName db 'cipher file read and write',0dh,0ah,'$'

namepar label byte maxlen db 30 namelen db ? namerec db 30 dup(' '),0dh,0ah

clrf db 13,10,'$' errcde db 0 handle dw ?

pathMaxLen db 50 pathActLen db ? pathnam db 'd:\masm5\409\mydata.txt',0

prompt db 'name? ' row db 01 opnmsg db '***open error***',0dh,0ah,'$' wrtmsg db '***write error***',0dh,0ah,'$' mykey db 6Ch .code begin proc far

mov ax,@data mov ds,ax mov es,ax mov ax,0600h

call scren call curs call showmyinfo

call creath cmp errcde,0 jz contin jmp back

contin: call proch cmp namelen,0 jne contin call clseh

back: mov ax,4c00h int 21h begin endp

creath proc near mov ah,3ch mov cx,0 lea dx,pathnam int 21h jc a1

mov handle,ax ret

a1: lea dx,opnmsg call errm ret creath endp

proch proc near mov ah,40h mov bx,01 mov cx,06 lea dx,prompt int 21h

mov ah,0ah lea dx,namepar int 21h cmp namelen,0 jne b1 ret

b1: mov al,20h sub ch,ch mov cl,namelen lea di,namerec add di,cx neg cx add cx,30 cld rep stosb ;-------------------------- mov si,0 mov al,myKey mov cx,30 cipher1: xor namerec[si],al inc si loop cipher1 ;---------------------------

call writh call scrl ret proch endp

scrl proc near cmp row,18h jae c1 mov ah,09 lea dx,clrf int 21h inc row ret c1: mov ax,0610h call scren call curs ret scrl endp

writh proc near mov ah,40h mov bx,handle mov cx,32 lea dx,namerec int 21h jnc d1 lea dx,wrtmsg call errm mov namelen,0 d1: ret writh endp

clseh proc near mov namerec,1ah call writh mov ah,3eh mov bx,handle int 21h ret clseh endp

scren proc near mov bh,1eh mov cx,0 mov dx,184fh int 10h ret scren endp

curs proc near mov ah,02 mov bh,0 mov dh,row mov dl,0 int 10h ret curs endp errm proc near mov ah,40h mov bx,01 mov cx,21 int 21h mov errcde,01 ret errm endp

showmyinfo proc near push dx lea dx,myname mov ah,9 int 21h pop dx ret showmyinfo endp

end begin 2．读取文件 .model small .stack 64 .data endcde db 0 handle dw ? ioarea db 32 dup(' ') pathnam db 'd:\masm5\409\mydata.txt',0 openmsg db '***open error***',0dh,0ah readmsg db '***read error***',0dh,0ah row db 0 myKey db 6Ch .code begin proc far mov ax,@data mov ds,ax mov es,ax mov ax,0600h call scren call curs call openh cmp endcde,0 jnz a1

contin: call readh cmp endcde,0 jnz a1

call disph jmp contin a1: mov ax,4c00h int 21h begin endp

openh proc near mov ah,3dh mov al,0 lea dx,pathnam int 21h jc b1 mov handle,ax ret b1: mov endcde,01 lea dx,openmsg call errm ret openh endp

readh proc near mov ah,3fh mov bx,handle mov cx,32 lea dx,ioarea int 21h ;-------------------------- mov si,0 mov al,myKey mov cx,30 uncipher1: xor ioarea[si],al inc si loop uncipher1 ;--------------------------- jc c1 cmp ax,0 je c2 cmp ioarea,1ah je c2 ret c1: lea dx,readmsg call errm

c2: mov endcde,01 ret readh endp

disph proc near mov ah,40h mov bx,01 mov cx,32 lea dx,ioarea int 21h cmp row,24 jae d1 inc row ret d1: mov ax,0601h call scren call curs ret disph endp

scren proc near mov bh,1eh mov cx,0 mov dx,184fh int 10h ret scren endp

curs proc near mov ah,2 mov bh,0 mov dh,row mov dl,0 int 10h ret curs endp

errm proc near mov ah,40h mov bx,01