* $Revision Header *** Header built automatically - do not edit! ***********
 *
 *	(C) Copyright 1992 by Torsten Jürgeleit
 *
 *	Name .....: files2.asm
 *	Created ..: Wednesday 22-Oct-92 15:23:51
 *	Revision .: 0
 *
 *	Date        Author                 Comment
 *	=========   ====================   ====================
 *	22-Oct-92   Torsten Jürgeleit      Created this file!
 *
 ****************************************************************************
 *
 *	DOS calls between open and close of dos library -> neccessary for
 *	DOS calls from within intuisup.library
 *
 * $Revision Header ********************************************************/

;---------------------------------------------------------------------------
; Support macros
;---------------------------------------------------------------------------

PUSH	MACRO
	movem.l	\1,-(sp)
	ENDM

PULL	MACRO
	movem.l	(sp)+,\1
	ENDM

CALLSYS	MACRO
	XREF	_LVO\1
	jsr	_LVO\1(a6)
	ENDM

;---------------------------------------------------------------------------
; External definitions
;---------------------------------------------------------------------------

	XDEF	_dos_open
	XDEF	_dos_read
	XDEF	_dos_close

;---------------------------------------------------------------------------
; BPTR dos_open(BYTE *name, LONG flags)
;                    a0         d0
;---------------------------------------------------------------------------

_dos_open:
	PUSH	d2-d3/a2/a6

	; --- save parameters
	move.l	a0,a2			; a2 := file name ptr
	move.l	d0,d2			; d2 := flags
	moveq	#0,d3			; d3 := return code

	; --- open dos library
	move.l	(4).w,a6		; a6 := SysBase
	lea	dos_name(pc),a1		; a1 := library name
	moveq	#0,d0			; d0 := version
	CALLSYS	OpenLibrary
	tst.l	d0
	beq.s	do_exit

	; --- call DOS function Open()
	move.l	d0,a6			; a6 := DosBase
	move.l	a2,d1			; d1 := file name ptr
					; d2 := flags
	jsr	-$1e(a6)		; CALLSYS Open -> Bug in c16.lib (POSITIVE lib offset)
	move.l	d0,d3			; d3 := BPTR to file handle

	; --- close dos library
	move.l	a6,a1			; a1 := DosBase
	move.l	(4).w,a6		; a6 := SysBase
	CALLSYS	CloseLibrary

do_exit:
	; --- prepare return code
	move.l	d3,d0

	PULL	d2-d3/a2/a6
	rts

;---------------------------------------------------------------------------
; LONG dos_read(BPTR fh, BYTE *buffer, LONG size);
;                  a0         a1          d0
;---------------------------------------------------------------------------

_dos_read:
	PUSH	d2-d4/a2-a3/a6

	; --- save parameters
	move.l	a0,a2			; a2 := BPTR to file handle
	move.l	a1,a3			; a3 := buffer ptr
	move.l	d0,d3			; d3 := size
	moveq	#-1,d4			; d4 := return code

	; --- open dos library
	move.l	(4).w,a6		; a6 := SysBase
	lea	dos_name(pc),a1		; a1 := library name
	moveq	#0,d0			; d0 := version
	CALLSYS	OpenLibrary
	tst.l	d0
	beq.s	dr_exit

	; --- call DOS function Read()
	move.l	d0,a6			; a6 := DosBase
	move.l	a2,d1			; d1 := BPTR to file handle
	move.l	a3,d2			; d2 := buffer ptr
					; d3 := size
	jsr	-$2a(a6)		; CALLSYS Read -> Bug in c16.lib (POSITIVE lib offset)
	move.l	d0,d4			; d4 := num of characters read

	; --- close dos library
	move.l	a6,a1			; a1 := DosBase
	move.l	(4).w,a6		; a6 := SysBase
	CALLSYS	CloseLibrary

dr_exit:
	; --- prepare return code
	move.l	d4,d0

	PULL	d2-d4/a2-a3/a6
	rts

;---------------------------------------------------------------------------
; VOID dos_close(BPTR fh);
;                   a0
;---------------------------------------------------------------------------

_dos_close:
	PUSH	a2/a6

	; --- save parameters
	move.l	a0,a2			; a2 := BPTR to file handle

	; --- open dos library
	move.l	(4).w,a6		; a6 := SysBase
	lea	dos_name(pc),a1		; a1 := library name
	moveq	#0,d0			; d0 := version
	CALLSYS	OpenLibrary
	tst.l	d0
	beq.s	dc_exit

	; --- call DOS function Close()
	move.l	d0,a6			; a6 := DosBase
	move.l	a2,d1			; d1 := BPTR to file handle
	jsr	-$24(a6)		; CALLSYS Close -> Bug in c16.lib (POSITIVE lib offset)

	; --- close dos library
	move.l	a6,a1			; a1 := DosBase
	move.l	(4).w,a6		; a6 := SysBase
	CALLSYS	CloseLibrary

dc_exit:
	PULL	a2/a6
	rts

;---------------------------------------------------------------------------
; Static data
;---------------------------------------------------------------------------

dos_name:
	dc.b	"dos.library"

	END