feat(write): adding the write function in asm
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21
src/ft_write.s
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21
src/ft_write.s
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segment .note.GNU-stack
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extern __errno_location
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section .text
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global ft_write
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ft_write:
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mov rax, 1 ; syscall 1 is for write
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syscall ; call the system call write
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cmp rax, 0 ; check if the return value of syscall
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jl .error ; jump if the return value is less than 0
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ret ; return the value of the syscall
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.error:
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mov rdi, rax ; stock errno value in rdi
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neg rdi ; errno value in positive (index used by C function)
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call __errno_location ; rax = &errno
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mov [rax], edi ; stock the errno return in the address of rax
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mov rax, -1 ; set the value of rax to -1
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ret ; return with -1 (and errno value)
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