36 lines
570 B
ArmAsm
36 lines
570 B
ArmAsm
; Returns length in rax
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; Errors (in rax):
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; -1024 - line too long
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; other negative - error from read(2)
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; Arguments:
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; rdi - fd
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; rsi - buffer
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; rdx - max length
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readline:
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push rdi
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push rsi
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push rdx
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mov rax, SYS_READ
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syscall
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pop rdx
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pop rsi
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pop rdi
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cmp rax, 0
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jl return
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mov r10, 0
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readline__scan:
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cmp r10, rax
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jge readline__overflow
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mov r11b, [rsi + r10]
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add r10, 1
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cmp r11b, 0x0a ; '\n'
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jne readline__scan
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readline__return:
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mov rax, r10
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ret
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readline__overflow:
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mov rax, -1024
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ret
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