www.pudn.com > schdgurd.zip > FDOG.ASM

code segment 
     assume cs:code;ds:code 
     org 100h 
start:jmp init 
old13h dd ? 
buf db 512 dup(0) 
lmsg db 'Babysoft  (R) Floppy Disk Dog version 1.0',0Ah,0Dh 
     db 'Copyright (C) 1997.11 LiuYaDing,Babysoft Corp.',0Ah,0Dh,'$' 
hhmsg db 'Floppy Disk Dog installed.',0Ah,0Dh,'$' 
jxok db 'Floppy Disk Dog has installed flag on disk.',0Ah,0Dh,'$' 
msg db 'Invalid floppy!!!' 
dev db 0 
jsz db 0 
set dd 0ffff0000h 
new13h proc far 
    pushf 
    cmp ah,2 
    jb old 
    cmp ah,3 
    ja old 
    cmp dl,80h 
    jz old 
    jmp jx 
old:popf 
    jmp cs:old13h 
jx: popf 
    pushf 
    push ds 
    push es 
    push ax 
    push bx 
    push cx 
    push dx 
    push si 
    push di 
    mov ax,cs 
    mov ds,ax 
    mov es,ax 
    mov dev,dl 
    mov jsz,3 
    mov ax,201h 
    mov cx,2 
    mov dh,0 
    mov bx,offset buf 
    pushf 
    call cs:old13h 
readfat: 
    mov ax,201h 
    mov cx,2 
    mov dh,0 
    mov bx,offset buf 
    pushf 
    call cs:old13h 
    jnc cmpid 
    cmp jsz,3 
    jz cmpid 
    dec jsz 
    mov ax,0e07h 
    int 10h 
    mov ah,0 
    mov dl,dev 
    call cs:old13h 
    pushf 
    jmp readfat 
cmpid: 
    mov ax,word ptr [buf+1] 
    cmp ax,3456h 
    jz oold 
    mov ah,3 
    mov bh,0 
    int 10h 
    push dx 
    mov dx,30h 
    lea si,msg 
    mov cx,17 
loop1: 
    mov ah,2 
    int 10h 
    mov bl,70h 
    mov ah,9 
    lodsb 
    int 10h 
    inc dl 
    loop loop1 
    mov ah,2 
    pop dx 
    int 10h 
    mov ah,0 
    int 16h 
    or al,20h 
    cmp al,'y' 
    jnz reset 
    pop di 
    pop si 
    pop dx 
    pop cx 
    pop bx 
    pop ax 
    pop es 
    pop ds 
    popf 
    mov ah,4ch 
    int 21h 
reset: 
    mov bx,0 
    mov si,0 
    xor ax,ax 
    mov ds,ax 
    mov word ptr ds:[472h],1234h 
    push cs 
    pop ds 
    jmp set[bx][si] 
oold: 
    pop di 
    pop si 
    pop dx 
    pop cx 
    pop bx 
    pop ax 
    pop es 
    pop ds 
    popf 
    assume ds:nothing 
    jmp cs:old13h 
new13h endp 
init: 
    push cs 
    pop ds 
    mov dx,offset lmsg 
    mov ah,9 
    int 21h 
    mov si,80h 
    mov al,[si] 
    cmp al,0 
    jz zl 
    mov si,82h 
    mov al,[si] 
    and al,0fh 
    dec al 
    cmp al,1 
    ja error 
    push ax 
    mov cx,1 
    mov dx,1 
    mov bx,offset buf 
    int 25h 
    mov ax,3456h 
    mov word ptr [buf+1],ax 
    popf 
    pop ax 
    mov cx,1 
    mov dx,1 
    int 26h 
    jnc exit 
error: 
    mov ah,9 
    mov dx,offset er 
    int 21h 
    mov ax,4c00h 
    int 21h 
exit: 
    mov dx,offset jxok 
    mov ah,9 
    int 21h 
    mov ax,4c00h 
    int 21h 
er db 07h,'Write-protected or Invalid driver!',0Ah,0Dh,'$' 
zl: mov ax,3513h 
    int 21h 
    mov di,bx 
    mov si,offset new13h 
    mov cx,offset init 
    sub cx,si 
    cld 
    repz cmpsb 
    jnz zl1 
    mov dx,offset hmsg 
    mov ah,9 
    int 21h 
    mov ax,4c00h 
    int 21h 
hmsg: 
    db 07h,'Floppy Disk Dog has already installed!',0Ah,0Dh,'$' 
zl1: 
    mov dx,offset hhmsg 
    mov ah,9 
    int 21h 
    mov word ptr old13h,bx 
    mov word ptr old13h+2,es 
    mov dx,offset new13h 
    mov ax,2513h 
    int 21h 
    mov dx,offset init 
    int 27h 
code ends 
     end start