73 lines
1.0 KiB
Plaintext
73 lines
1.0 KiB
Plaintext
bits 32
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section .data
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stdout equ 1
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sys_write equ 4
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sys_exit equ 1
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kernel equ 0x80
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program db "Program: ", 0
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programlen equ $-program
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nl db "", 10, 0
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nllen equ $-nl
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section .bss
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scriptname resd 1
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scriptnamelen resd 1
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section .text
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global _start
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strlen: ; eax: a string ending in 0
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push eax ; cache eax
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.strloop:
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mov bl, byte [eax]
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cmp bl, 0
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je .strret ; return len if bl == 0
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inc eax ; else eax++
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jmp .strloop
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.strret:
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pop ebx ; ebx = cached eax
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sub eax, ebx ; eax -= ebx
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ret ; eax = len
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_start:
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mov eax, esp
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add eax, 4
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mov eax, [eax]
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mov dword [scriptname], eax
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mov eax, sys_write
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mov ebx, stdout
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mov ecx, program
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mov edx, programlen
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int kernel
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mov dword eax, [scriptname]
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call strlen
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mov dword [scriptnamelen], eax
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mov eax, sys_write
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mov ebx, stdout
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mov dword ecx, [scriptname]
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mov dword edx, [scriptnamelen]
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int kernel
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mov eax, sys_write
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mov ebx, stdout
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mov ecx, nl
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mov edx, nllen
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int kernel
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mov eax, sys_exit
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mov ebx, 0
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int kernel
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