73 lines
1.9 KiB
NASM
73 lines
1.9 KiB
NASM
bits 32 ; assembling for the 32 bits architecture
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; declare the EntryPoint (a label defining the very first instruction of the program)
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global start
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; declare external functions needed by our program
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extern exit,fopen,fclose,printf,fread,strchr ; tell nasm that exit exists even if we won't be defining it
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import exit msvcrt.dll ; exit is a function that ends the calling process. It is defined in msvcrt.dll
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import fopen msvcrt.dll
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import fclose msvcrt.dll
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import printf msvcrt.dll
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import fread msvcrt.dll
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import strchr msvcrt.dll
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; our data is declared here (the variables needed by our program)
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;A text file is given. Read the content of the file, count the number of vowels and display the result on the screen. The name of text file is defined in the data segment.
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segment data use32 class=data
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; ...
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file_path db "text.txt",0
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access_mode db "r",0
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vowels db "aeiouAEIOU",0
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message db "The number of vowels in the file is: %d",0
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file dd 0
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a db 0
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count dd 0
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; our code starts here
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segment code use32 class=code
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start:
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; ...
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push dword access_mode
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push dword file_path
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call [fopen]
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add ESP,4*2
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cmp EAX,0
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jz end
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mov [file],EAX
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push dword [file]
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push dword 1
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push dword 1
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push dword a
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loop_label:
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call [fread]
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cmp EAX,0
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jz done
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push dword [a]
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push dword vowels
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call [strchr]
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add ESP,4*2
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cmp EAX,0
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jz loop_label
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inc dword [count]
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jmp loop_label
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done:
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add ESP,4*4
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; exit(0)
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push dword [file]
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call [fclose]
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add ESP,4*1
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push dword [count]
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push dword message
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call [printf]
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add ESP,4*2
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end:
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push dword 0 ; push the parameter for exit onto the stack
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call [exit] ; call exit to terminate the program
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