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%ifndef _TERMINAL_ASM
%define _TERMINAL_ASM
MAXBUF equ 254
terminal:
push bp
mov bp, sp
;sub sp, MAXBUF ; allocate large string buffer
.clear_buffer:
mov cx, MAXBUF
mov bx, t_buffer
mov di, bx
.cl:
mov [di], byte 0
inc di
dec cx
jne .cl
mov di, bx
.do_prompt:
mov cx, 0
mov al, CR
call putc
push t_msg_prompt
push t_msg_prompt_fmt
call printf
add sp, 4
mov di, t_buffer
.read_command:
call kbd_read
.update_buffer:
cmp al, CR
je .dump_buffer
stosb
inc cx
jmp .output
.dump_buffer:
cmp [di-1], byte 0
je .do_prompt
mov al, CR
call putc
push t_buffer ; push onto stack
push t_buffer_fmt
call printf ; write out string
add sp, 4
jmp .clear_buffer
.output:
call putc
jmp .read_command
jmp .do_prompt
mov sp, bp
pop bp
ret
; data
t_msg_prompt_fmt: db '%s', 0
t_msg_prompt: db '$ ', 0
t_buffer_fmt: db '%s', 0
t_buffer: times MAXBUF db 0
%endif
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