27 lines
610 B
ArmAsm
27 lines
610 B
ArmAsm
global ft_write
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extern __errno_location
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ft_write:
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cmp rsi, 0 ; if buffer is null
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je .bad_buff ; goto bad_buff
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mov eax, 0x1 ; put the syscall number of write
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syscall ; call write
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test rax, rax ; test if the syscall failed
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js .error
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ret
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.bad_buff:
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mov rdx, 22 ; put the corresponding errno code
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call __errno_location wrt ..plt
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mov [rax], rdx
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mov rax, -1
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ret
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.error:
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mov rdx, rax ; move the syscall return value
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call __errno_location wrt ..plt
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neg rdx ; we neg the syscall return value to put it in errno
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mov [rax], rdx ; *errno_location = value
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mov rax, -1 ; we return -1
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ret
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