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%include "unistd.asm"
%include "utils.asm"
stdout equ 1
global _start
section .text
_start:
mov rcx, [rsp] ; Get number of arguments
mov rdi, [rsp + rcx * 8] ; Get last argument
mov rax, SYS_access ; Check if file exists and is readable
mov esi, R_OK
syscall
test rax, rax
jnz .exit_err
mov rax, SYS_open
xor esi, esi
xor edx, edx
syscall
mov r8d, eax ; Move fd into r8
mov rax, SYS_mmap
xor edi, edi ; Let the kernel choose the address
mov rsi, 12288
mov rdx, PROT_READ
mov r10d, MAP_PRIVATE
xor r9d, r9d
syscall
cmp rax, -1 ; Exit on error
je .exit_err
xor r13d, r13d
mov r12d, ~0
mov rdi, rax
.loop:
call atoi
cmp eax, r12d
jna .na
inc r13d
.na:
mov r12d, eax
cmp byte [rdi], 0
je .exit
inc rdi
cmp byte [rdi], 0
jne .loop
.exit:
mov edi, stdout
mov esi, r13d
call write_ulong
mov rax, SYS_exit
xor edi, edi
syscall
.exit_err:
mov rax, SYS_exit
mov edi, 1
syscall
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