;
; Maciej 'YTM/Elysium' Witkowiak
;
; 25.12.99

	    .export DB_get2lines
	    .importzp ptr3,ptr4
	    .import popax

.code

DB_get2lines:
	    sta ptr4		; fetch line 2
	    stx ptr4+1
	    jsr popax
	    sta ptr3		; fetch line 1
	    stx ptr3+1
	    ldx ptr3
	    jsr checknull
	    ldx ptr4
	    jmp checknull

checknull:
	    lda $0,x
	    ora $1,x
	    bne cn_end
	    lda #<nullstring
	    sta $0,x
	    lda #>nullstring
	    sta $1,x
cn_end:	    rts

.rodata

nullstring:
	    .byte 0