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+**
+**	$Id: $
+**	$Revision: $
+**
+**	$Filename: OpenIFF.S $
+**	$Author: Christian A. Weber $
+**	$Release: 19.1 $
+**	$Date: 92/05/11 21:11:27 $
+**
+**	iff.library/IFFLib_OpenIFF
+**
+**	COPYRIGHT (C) 1987-1992 BY CHRISTIAN A. WEBER, BRUGGERWEG 2,
+**	CH-8037 ZUERICH, SWITZERLAND.  ALL RIGHTS RESERVED.  NO PART
+**	OF THIS SOFTWARE MAY BE COPIED, REPRODUCED,  OR  TRANSMITTED
+**	IN ANY FORM OR BY ANY MEANS,  WITHOUT THE PRIOR WRITTEN PER-
+**	MISSION OF THE AUTHOR. USE AT YOUR OWN RISK.
+**
+
+
+		IDNT	IFFLib_OpenIFF
+		SECTION	text,CODE
+
+		INCLUDE	"IFFLib.i"
+
+		XREF	SetError,ClearError
+		XDEF	OpenIFFFunc,NewOpenIFFFunc
+
+
+******* iff.library/IFFLib_NewOpenIFF ***************************************
+*
+*   NAME
+*	IFFLib_NewOpenIFF -- allocate memory for an IFF-file and read it
+*
+*   SYNOPSIS
+*	ifffile = IFFLib_NewOpenIFF( filename, memattr )
+*	D0                           A0        D0
+*
+*	IFFFILE IFFLib_OpenIFF( char * )
+*
+*   FUNCTION
+*	This function opens a file on a disk and looks whether it's an IFF
+*	file or not. If it is an IFF file, memory is allocated and the file
+*	is read into memory. The 'memattr' argument is taken to define the
+*	memory type. Normally memattr is set to MEMF_ANY or MEMF_PUBLIC.
+*	If an error occurs, NULL is returned, and you can call
+*	IFFLib_IFFError() to get the error number.
+*
+*   INPUTS
+*	filename - Pointer to a null-terminated string
+*	memattr  - Memory requirements as used for Exec's AllocMem(),
+*	           such as MEMF_CHIP, MEMF_PUBLIC ...
+*	           (MEMF_CLEAR is not necessary)
+*
+*   RESULT
+*	ifffile - 'FileHandle', points to the beginning of the IFF file
+*	("FORM...."), Zero if unsuccessful. Call IFFLib_IFFError() to get
+*	the reason of the failure.
+*
+*   SEE ALSO
+*	IFFLib_OpenIFF(), IFFLib_CloseIFF(), IFFLib_IFFError()
+*
+*   BUGS
+*	None known
+*
+*****************************************************************************
+
+OpenIFFFunc:	movem.l	d2-d6/a2/a5-a6,-(SP)
+		moveq.l	#-1,d6			; Kein MemType angegeben
+		bra.s	DoCont
+
+
+
+******* iff.library/IFFLib_OpenIFF ******************************************
+*
+*    NAME
+*	IFFLib_OpenIFF -- allocate memory for an IFF-file and read it
+*
+*    SYNOPSIS
+*	ifffile = IFFLib_OpenIFF( filename )
+*	D0                        A0
+*
+*	IFFFILE IFFLib_OpenIFF( char * )
+*
+*    FUNCTION
+*	This function does the same as the IFFLib_NewOpenIFF() routine
+*	above, except that you cannot specify the type of memory which is
+*	allocated for the file. Normally the type is 0 which means 'any
+*	memory', but if the IFF file type is '8SVX', the file is ALWAYS
+*	loaded into CHIP memory. If you wish to override these defaults,
+*	use IFFLib_NewOpenIFF() instead of IFFLib_OpenIFF().
+*
+*   INPUTS
+*	filename - Pointer to a null-terminated string
+*
+*   RESULT
+*	ifffile - 'FileHandle', points to the beginning of the IFF file
+*	("FORM...."), 0 if unsuccessful. Call IFFError() to get the
+*	reason of the failure.
+*
+*   BUGS
+*	None
+*
+*   SEE ALSO
+*	IFFLib_NewOpenIFF(), IFFLib_CloseIFF(), IFFLib_IFFError()
+*
+*****************************************************************************
+
+NewOpenIFFFunc:	movem.l	d2-d6/a2/a5-a6,-(SP)
+		move.l	d0,d6			; D6 :  MemType
+DoCont:		movea.l	a6,a5			; IFFBase
+		lea	-12(SP),SP		; Arbeitsspeicher reservieren
+		moveq.l	#0,d5			; Fehlernummer rücksetzen
+
+	*** File öffnen
+
+		move.l	a0,d1			; Name
+		move.l	#MODE_OLDFILE,d2	; accessmode
+		movea.l	ib_DOSBase(a5),a6
+		JSRLIB	Open
+		move.l	d0,d4			; D4 := FileHandle
+		bne.s	1$
+		moveq	#IFF_CANTOPENFILE,d5
+		bra.s	.Error2			; --->
+1$:
+	*** Erste 12 Bytes lesen, testen ob 'FORM'
+
+		move.l	d4,d1			; File
+		move.l	SP,d2			; Adr
+		moveq.l	#12,d3			; Len
+		JSRLIB	Read			; erste 3 Longwords lesen
+		cmpi.l	#'FORM',(SP)
+		beq.s	2$
+		moveq	#IFF_NOTIFF,d5
+		bra.s	.Error1			; --->
+2$:
+	*** Testen ob Chip-Speicher erwünscht (bei 8SVX-Files)
+
+		move.l	d6,d1			; Default-Requirements
+		bpl.s	3$			; sind gültig --->
+		moveq.l	#MEMF_PUBLIC,d1
+		cmpi.l	#'8SVX',8(SP)		; 8SVX-File ?
+		bne.s	3$			; nein --->
+		moveq.l	#MEMF_CHIP|MEMF_PUBLIC,d1 ; sonst CHIP-Memory!
+3$:
+	*** Speicher für File reservieren
+
+		moveq.l	#12,d2			; 'Remember' + FORM....
+		move.l	4(SP),d3		; D3 :  FORM-Länge
+		add.l	d3,d2			; D2 :  Gesamtlänge
+		subq.l	#4,d3	; FUCK!!! IFF-Typ ist ja schon gelesen!
+		move.l	d2,d0
+		movea.l	ib_SysBase(a5),a6
+		JSRLIB	AllocMem		; requirements von D1
+		movea.l	d0,a2			; A2 :  IFFFile-Adresse
+		tst.l	d0
+		bne.s	4$			; OK --->
+		moveq	#IFF_NOMEM,d5
+		bra.s	.Error1			; --->
+4$:
+	*** File einladen
+
+		move.l	d2,(a2)+		; Länge des reserv. Bereichs
+		move.l	d4,d1			; File
+		move.l	a2,d2			; Adr
+		addq.l	#8,d2			; FORM.... schon gelesen!
+		addq.l	#4,d2			; IFF-Typ schon gelesen
+		movea.l	ib_DOSBase(a5),a6
+		JSRLIB	Read			; D3 war schon Länge
+		tst.l	d0
+		bpl.s	5$			; OK --->
+		moveq	#IFF_READERROR,d5
+		bra.s	.Error1
+5$:
+		movem.l	(SP),d0-d2		; FORM, Länge und Type
+		movem.l	d0-d2,(a2)		; IFF-Filetyp
+
+.Error1:	move.l	d4,d1			; File
+		movea.l	ib_DOSBase(a5),a6
+		JSRLIB	Close
+
+.Error2:	move.l	d5,d0			; Error ?
+		beq.s	6$			; nein --->
+		bsr	SetError		; Löscht auch D0
+		bra.s	Ende
+6$:
+		bsr	ClearError
+		move.l	a2,d0			; Adresse als Return-Code
+Ende:
+		lea	12(SP),SP		; Lokalen Speicher freigeben
+		movem.l	(SP)+,d2-d6/a2/a5-a6
+		rts
+
+		END