mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-18 17:36:11 +00:00
112 lines
3.9 KiB
NASM
112 lines
3.9 KiB
NASM
title FREE.ASM
|
||
page,132
|
||
|
||
cseg segment para 'code'
|
||
assume cs:cseg
|
||
main proc far
|
||
org 100h
|
||
start:
|
||
jmp begin
|
||
|
||
banner db 0ah,'FREE Vers 1.0 - Sept. 1985 - by Art Merrill',0dh,0ah,'$'
|
||
db 'Copyright (C) 1985',0dh,0ah,'$'
|
||
db 'Ziff-Davis Publishing Company',0dh,0ah,'$'
|
||
total: db 0ah,8 dup(0),' bytes total disk space',0dh,0ah
|
||
diff: db 8 dup(0),' bytes allocated',0dh,0ah
|
||
bytes: db 8 dup(0),' bytes available on disk',0dh,0ah,0ah,'$'
|
||
hltotal: dw 0,0
|
||
hlbytes: dw 0,0
|
||
|
||
begin:
|
||
mov dx,offset banner
|
||
mov ah,9
|
||
int 21h
|
||
|
||
mov si,5ch ;address of selected drive
|
||
mov dl,[si]
|
||
mov ah,36h ;get disk free space
|
||
int 21h
|
||
|
||
push ax ;save for total bytes
|
||
push cx ;save for total bytes
|
||
push dx ;save for total bytes
|
||
|
||
mul bx ;get total clusters
|
||
mul cx ;get total bytes
|
||
|
||
std
|
||
mov di,offset hlbytes+2
|
||
xchg ax,dx
|
||
stosw
|
||
xchg ax,dx
|
||
stosw
|
||
|
||
mov di,offset bytes+7 ;storage for ascii printout
|
||
call ascii
|
||
|
||
pop dx ;get back total clusters
|
||
pop cx ;get back bytes per sector
|
||
pop ax ;get back sectors per cluster
|
||
|
||
mul dx ;total clusters
|
||
mul cx ;bytes per sector
|
||
|
||
mov di,offset hltotal+2 ;same routine as above to get
|
||
xchg ax,dx ; total bytes
|
||
stosw
|
||
xchg ax,dx
|
||
stosw
|
||
|
||
mov di,offset total+8 ;storage for ascii printout
|
||
call ascii
|
||
|
||
mov ax,word ptr hltotal+2 ;calculate difference between
|
||
sub ax,word ptr hlbytes+2 ; total bytes and bytes allocated
|
||
xchg ax,dx ; to get total bytes remaining
|
||
mov ax,word ptr hltotal
|
||
sub ax,word ptr hlbytes
|
||
jnc skip
|
||
dec dx ;adjust total for carry
|
||
skip:
|
||
mov di,offset diff+7 ;storage for ascii printout
|
||
call ascii
|
||
|
||
mov dx,offset total ;print results
|
||
mov ah,9
|
||
int 21h
|
||
|
||
int 20h ;exit
|
||
|
||
main endp
|
||
|
||
ascii proc near
|
||
xchg bp,dx ;save high word
|
||
mov bx,0ah ;divisor
|
||
mov cl,30h ;conversion for ascii
|
||
rpt1:
|
||
cmp bp,0 ;are we done with high words
|
||
jz rpt2 ;yes
|
||
xchg ax,bp ;no-get high word
|
||
xor dx,dx ;clear dx
|
||
div bx
|
||
xchg bp,ax ;this will be the new high word
|
||
div bx ;divide low word + remainder
|
||
or dl,cl ;convert hex value to ascii
|
||
mov [di],dl ;quotient into storage
|
||
dec di ;step back one byte
|
||
jmp rpt1 ;go again
|
||
rpt2:
|
||
xor dx,dx ;clear dx
|
||
div bx
|
||
or dl,cl ;convert hex value to ascii
|
||
mov [di],dl ;quotient into storage
|
||
dec di ;step back one byte
|
||
cmp ax,0 ;are we done?
|
||
jnz rpt2 ;no
|
||
|
||
ret ;yes
|
||
ascii endp
|
||
|
||
cseg ends
|
||
end start
|
||
|