33 lines
418 B
NASM
33 lines
418 B
NASM
%define fd_num 32
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section .bss
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fd_table: resb (0x10 * fd_num)
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section .text
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fd_to_ptr: push cx
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mov cl, 4
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sal bx, cl
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add bx, fd_table
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pop cx
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ret
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fd_read: cmp bx, fd_num
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jnc fd_inv_hnd
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call fd_to_ptr
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; read ptr to ftab
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mov bx, [bx]
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; jmp to addr in ftab[0]
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jmp [bx]
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fd_write: cmp bx, fd_num
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jnc fd_inv_hnd
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call fd_to_ptr
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mov bx, [bx]
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jmp [bx+2]
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fd_inv_hnd: mov ax, 6
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stc
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ret
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