ASM SCAS - find a String except of character in buffer

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i am working on assembly project and i am trying some string operations. Problem that i encountered is with SCAS function. I am trying to search my text for specific string occurence or even substring occurence. I thought SCAS might fit this task. What i found about Scas is Basically this:

http://ift.tt/1agAwrp

The example there shows how a simple character can be found in a buffer. Thats nice and i can use it because i read my text file using buffer so i can search this buffer multiple times to find occurence of my string. Problem is that i can figure out the way how can i use custom strings instead of characters with SCAS.

In my code i am trying something like this

CYK:    

    CMP pomaxx,0                
    JZ  NACITAJ2                     
    DEC pomaxx
    MOV CX,BUFSIZ               
    MOV DX,OFFSET buff          
    MOV AH,3Fh                  
    INT 21h


    MOV     AX, DS
    MOV     ES, AX          ;SCAS uses ES:DI, so copy DS to ES
    CLD                     ;Scan in the forward direction
    MOV     AL, STRI      
    MOV     CX,BUFSIZ       ;Scanning 50 words (CX is used by REPNE)
    LEA     DI, buff      ;Starting address to DI
REPNE   SCAS    buff              ;   ...and scan it.
JE      FOUND           ;The Zero Flag will be set if we found  
                              ;   a match.


NOTFOUND:  JMP CYK                  ;If we get here, no match was found

FOUND:  

    MOV SI,OFFSET buff          ;DS:SI musi ukazovat na miesto z ktoreho chceme tahat
 CYKBUFSIZ2:
    LODSB                       
    PCHAR AL
    LOOP CYKBUFSIZ2

    JMP PRVY2

The last cycle is just generating output. So in this code i am trying to walk through my text fuile and buffer by buffer search my string and if i find the string i print the whole buffer. The STRI variable is defined as follows: STRI DB STRSIZ DUP(?). There i have my string i would like to find in my text file.

Can anyone help what am i doing wrong? Thx

asked 1 min ago

user3568104

8

ASM SCAS - find a String except of character in buffer