nolist
;:ts=8
*****************************************************************
*                                                               *
* VBRMove version 2.3, © 1991 Arthur Hagen, All rights reserved *
*                                                               *
* Posted to the Public Domain.                                  *
*                                                               *
* Written using the Aztec Manx C 5.0 Assembler                  *
*                                                               *
* All comments deliberately stripped from source.               *
* If you don't understand it, you should not mess with it!      *
*                                                               *
*****************************************************************

	include	'exec/memory.i'
	include	'exec/execbase.i'
	xref    _LVOOldOpenLibrary
	xref    _LVOCloseLibrary
	xref    _LVOSuperState
	xref	_LVOCopyMemQuick
	xref    _LVOOutput
	xref    _LVOWrite
	xref    _LVOAllocMem
	xref	_LVOFreeMem
	xref	_LVOPermit
INTENA	equ	$dff09a
	list

	machine	mc68010
	public	_VBRMove
_VBRMove:
	movea.l	(4).w,a6
	lea	INTENA,a3
	moveq	#64,d6
	rol.w	#4,d6
	lea	dosname(pc),a1
	jsr	_LVOOldOpenLibrary(a6)
	movea.l	d0,a5
	exg.l	a5,a6
	jsr	_LVOOutput(a6)
	exg.l	a5,a6
	move.l	d0,d7
	moveq	#title_end-title,d3
	lea	title(pc),a0
	bsr	wrt
	btst	#AFB_68010,AttnFlags+1(a6)
	bne.s	tryit

badCPU	moveq	#wrongpro_end-wrongpro,d3
	lea	wrongpro(pc),a0
	bra.s	writerr

tryit	jsr	_LVOSuperState(a6)
	movec	VBR,d4
	move.l	sp,USP
	movea.l	d0,sp
	andi.w	#$dfff,SR
	tst.l	d4
	bne.s	alrdy

	lea	MemList+LH_HEAD(a6),a0
	moveq	#0,d2
	moveq	#$3f,d3
	not.b	d3
	moveq	#0,d5
	not.b	d5

loopit1	movea.l	LN_SUCC(a0),a0
	tst.l	LN_SUCC(a0)
	beq.s	memdon1

	move.w	MH_LOWER(a0),d0

	cmp.w	d3,d0
	bcc.s	loopit1
	cmp.w	d5,d0
	bcs.s	loopit1

	lea	MH_FIRST(a0),a4
	lea	MH_FREE(a0),a2
	move.w	#$4000,(a3)
	addq.b	#1,IDNestCnt(a6)
	move.l	(a4),d2
	move.l	(a2),d3
	moveq	#0,d0
	move.l	d0,(a4)
	move.l	d0,(a2)

memdon1	move.l	d6,d0
	addq.l	#8,d0
	moveq	#MEMF_FAST|MEMF_PUBLIC,d1
	jsr	_LVOAllocMem(a6)
	tst.l	d2
	beq.s	memdon2

	move.l	d2,(a4)
	move.l	d3,(a2)
	subq.b	#1,IDNestCnt(a6)
	bge.s	memdon2
	move.w	#$c000,(a3)

memdon2	move.l	d0,d4
	beq.s	nofm

	andi.w	#$fff0,d4
	suba.l	a0,a0
	movea.l	d4,a1
	bsr.s	copy1k
	move.l	d4,d3
	bsr.s	setvbr

quit	movea.l	a5,a1
	jmp	_LVOCloseLibrary(a6)

nofm	moveq	#nofastmem_end-nofastmem,d3
	lea	nofastmem(pc),a0

writerr	pea	quit(pc)

wrt	move.l	a0,d2
	move.l	d7,d1
	exg.l	a5,a6
	jsr	_LVOWrite(a6)
	exg.l	a5,a6
	rts

alrdy	moveq	#already_end-already,d3
	lea	already(pc),a0
	bsr.s	wrt
	move.l	d4,a0
	suba.l	a1,a1
	bsr.s	copy1k
	moveq	#0,d3
	bsr.s	setvbr
	move.l	d4,a1
	move.l	d6,d0
	jsr	_LVOFreeMem(a6)
	bra.s	quit

copy1k	move.l	d6,d0
	jmp	_LVOCopyMemQuick(a6)

setvbr	jsr	_LVOSuperState(a6)
	movec	d3,VBR
	move.l	sp,USP
	movea.l	d0,sp
	andi.w	#$dfff,SR
	rts

	dc.b	'$VER: '
title	dc.b	'VBRMove 2.3 (24.4.94)',$0A,$0D
	dc.b	'Copyright ',$A9,' 1992 Arthur Hagen.',$0A
title_end
already	dc.b	'Clearing VBR.',$0A
already_end
wrongpro
	dc.b	'You need 68010 or higher!',$0A
wrongpro_end
nofastmem
	dc.b	"No fast memory!",$0A
nofastmem_end
dosname	dc.b	'dos.library',0
	even
	END