Push address for scanf

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zeritonik

Joined: 10 Jul 2022
Posts: 1

zeritonik 10 Jul 2022, 16:26

I want to input array using scanf, but I don't know the proper way to do push address of element.

Code:

LENGTH = 4
ELEMENT = 2
arr rw LENGTH
scanf_si db "%hi", 0

mov ecx, LENGTH
mov di, 0
input_arr:
push arr + di ; invalid expression
push scanf_si
call [scanf]
add di, ELEMENT
loop input_arr

If I store array address in register and push it, code will work fine, but I know, that address can be calculated this way in some situations. I want to know if I can push address without using registers[/b]

10 Jul 2022, 16:26

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20430
Location: In your JS exploiting you and your system

revolution 10 Jul 2022, 18:23

Code:

arr rb LENGTH ; you probably want to reserve bytes, not words
push arr ; use the address directly

10 Jul 2022, 18:23

AsmGuru62

Joined: 28 Jan 2004
Posts: 1660
Location: Toronto, Canada

AsmGuru62 10 Jul 2022, 21:19

Also, call to [scanf] will most likely destroy ECX register and LOOP instruction will continue for more times, or less, than needed.

10 Jul 2022, 21:19

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20430
Location: In your JS exploiting you and your system

revolution 10 Jul 2022, 21:59

I missed that you are using di as an index. You can do this:

Code:

mov di, arr
push di
;....
add di, ELEMENT
;...

10 Jul 2022, 21:59

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