assembly - Reading Hex as String -
im not in coding in assembly, need write in assembly anyways here trying do. (i'm using masm32)
.data msg db 31h, 00h, 32h, 00h, 33h ;convert string "123" .code start: invoke messagebox, 0, addr msg, 0, 0 call exitprocess end start as can see each character or byte separated null byte, can show 1 byte, "1" instead of "123"
if can concatenate each readable byte until reaches end of string.
mov ebx, offset msg mov ecx, ebx add ebx, 2 invoke lstrcat, ebx, ecx maybe add loop also, don't know better way code or if have better solution can share.
in order work on string, need know length of string. done using null terminate string. functions not take string length argument, 00h, , print string it, messagebox doing, printing "1" , seeing next character 00h, stops printing.
in case, there no null terminator @ end of string, can string length @ assembly time symbol "$" current value of location counter.
msg db 31h, 00h, 32h, 00h, 33h ;convert string "123" msg_len equ $ - msg which means, take address of $ , subtract address of msg, , replace msg_len value.
include masm32rt.inc .data msg db 31h, 00h, 32h, 00h, 33h ;convert string "123" msg_len equ $ - msg .data? msg_new db msg_len + 1 dup (?) .code start: xor ecx, ecx ; index source array xor edx, edx ; index dest array lea esi, msg lea edi, msg_new convertit: mov al, byte ptr[esi + ecx] ; byte @ pointer + index cmp al, 0 ; 0? jne @f ; no, add dest array inc ecx ; yes, increase source index jmp checkforend ; check see if @ end @@: mov byte ptr [edi + edx], al; add byte dest array inc ecx ; increase both indexes inc edx ; checkforend: cmp ecx, msg_len ; check end - if ecx == msg_len done jne convertit ; if ecx != msg_len, continue loop mov byte ptr [edi + edx], 0 ; don't forget null terminate dest string invoke messagebox, hwnd_desktop, offset msg_new, null, mb_ok invoke exitprocess, 0 end start this can done less code , "converting" string "in place" beyond scope here.
@nik, of love assembly , don't use else.
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