.z80

;Utility to load directory names into the DIR RSX for use by the CCP
;
;Copyright (c) 1984 - Jim Lopushinsky
;

bdos	equ	5
fcb	equ	5ch

setdir:
	ld	sp,stack		;set up local stack
	ld	de,scbpb
	ld	c,49
	call	bdos			;return SCB address
	ld	(scbase),hl		;save SCB address
	ld	a,(fcb+1)
	cp	' '			;any command line options?
	jp	nz,noroot		;jump if file spec
	ld	hl,rootdir		;point to default name (ROOT.DIR)
	ld	de,fcb+1
	ld	c,8
	call	move			;move it into place
noroot:
	ld	hl,fcb+1
	ld	de,off			;point to "OFF"
	ld	c,8
	call	comp			;does he want to remove dir table?
	jp	nz,notoff		;jump if he doesn't
	ld	hl,(bdos+1)
	call	delrsx			;remove the RSX just loaded
	ld	de,rsx66
	ld	c,60
	call	bdos			;see if DIR RSX exists
	or	a
	jp	z,isdir			;jump if ok.
	call	ilprt			;tell him the bad news
	db	'Directory names are not loaded',13,10,0
	rst	0
isdir:
	call	delrsx			;remove dir table
	call	ilprt
	db	'Directory names removed',13,10,0
	rst	0

;..............
;
;Here for normal load of directory table
;
notoff:
	ld	de,fcb+9
	ld	a,(de)
	ld	hl,dir
	ld	c,3
	cp	' '			;is file type specified?
	call	z,move			;if not, move DIR into place
	ld	de,fcb
	ld	c,15
	call	bdos			;open the file
	inc	a
	jp	nz,isfile		;jump if open ok
	ld	hl,(bdos+1)
	call	delrsx			;delete RSX just loaded
	call	ilprt
	db	'File not found.',13,10,0
	rst	0
isfile:
	ld	de,rsx66
	ld	c,60
	call	bdos			;see if old DIR RSX exists
	or	a
	jp	nz,nodir		;jump if no old DIR RSX exists
	ld	(diradr),hl
	ld	hl,(bdos+1)
	call	delrsx			;remove RSX just loaded
	jp	onward
nodir:
	ld	hl,(bdos+1)
	ld	l,1bh			;point to init flag in RSX
	ld	(hl),0ffh		;set DIR RSX as initialized
	ld	de,rsx66
	ld	c,60
	call	bdos			;get table load address
	ld	(diradr),hl
onward:
	ld	hl,(diradr)		;get table load address
	ld	l,1bh			;point to init flag
	ld	(hl),0			;reset it in case of errors
	ld	l,0eh			;point to remove flag
	ld	(hl),0ffh		;set remove flag in case of errors
	ld	l,0ffh
	inc	h			;calculate highest usable table address
	ld	(dirend),hl
	ld	hl,(diradr)		;get directory load address
	ex	de,hl
	ld	hl,rootbuf		;point to file buffer
	call	rootfill		;fill the buffer
	ld	(rootloc),a		;reset offset into buffer
	jp	nz,rootparse		;jump if not at end of file
eof:
	call	ilprt
	db	'Abnormal EOF reading directory file',13,10,0
errxit:
	ld	hl,(bdos+1)
	call	delrsx
	rst	0
findlf:
	call	rootbyte
	jp	z,done
	cp	10
	jp	nz,findlf
rootparse:
	push	de
	ld	b,9
rootnmove:
	call	rootbyte
	jp	z,done1
	call	chkdir
	ld	(de),a
	inc	de
	cp	';'
	jp	z,rootpass
	dec	b
	jp	nz,rootnmove
	jp	golf
rootpass:
	ld	b,9
rootpmove:
	call	rootbyte
	jp	z,eof
	call	chkdir
	cp	' '
	jp	z,rootdu
	ld	(de),a
	inc	de
	dec	b
	jp	nz,rootpmove
golf:
	pop	de
	jp	findlf
rootdu:
	xor	a
	ld	(de),a
	inc	de
	call	chkdir
rootblk:
	call	rootbyte
	jp	z,eof
	cp	' '
	jp	z,rootblk
	sub	'A'
	jp	m,golf
	cp	16
	jp	nc,golf
	ld	(rootdrv),a
	ld	b,0
rootu:
	call	rootbyte
	jp	z,eof
	cp	' '
	jp	z,rootudone
	sub	'0'
	jp	m,golf
	cp	10
	jp	nc,golf
	push	af
	ld	a,b
	add	a,a
	add	a,a
	add	a,b
	add	a,a
	ld	b,a
	pop	af
	add	a,b
	ld	b,a
	cp	16
	jp	nc,golf
	jp	rootu
rootudone:
	ld	a,b
	rept	4
	add	a,a
	endm
	ld	b,a
	ld	a,(rootdrv)
	or	b
	ld	(de),a
	inc	de
	pop	bc
	jp	findlf
done1:
	pop	de
done:
	call	chkdir
	xor	a
	ld	(de),a
	ld	hl,(diradr)
	ld	l,1bh
	ld	(hl),0ffh
	ld	l,0eh
	ld	(hl),0
	call	ilprt
	db	'Directory table initialized',13,10,0
	rst	0

rootbyte:
	push	hl
	push	de
	push	bc
	ld	a,(rootloc)
	or	a
	jp	p,norootf
	call	rootfill
	jp	z,rootnon
norootf:
	inc	a
	ld	(rootloc),a
	dec	a
	call	addhla
	ld	a,(hl)
	and	7fh
	cp	26
rootnon:
	pop	bc
	pop	de
	pop	hl
	ret

rootfill:
	push	hl
	push	de
	ex	de,hl
	ld	c,26
	call	bdos
	ld	de,fcb
	ld	c,20
	call	bdos
	pop	de
	pop	hl
	or	a
	jp	z,goodr
	xor	a
	ret
goodr:
	inc	a
	ld	a,0
	ret

addhla:
	add	a,l
	ld	l,a
	ret	nc
	inc	h
	ret

chkdir:
	push	af
	push	hl
	ld	hl,(dirend)
	call	cphlde
	pop	hl
	jp	nc,dirok
	call	ilprt
	db	'Too many directory table entries',13,10,0
	jp	errxit
dirok:
	pop	af
	ret

cphlde:
	ld	a,h
	cp	d
	ret	nz
	ld	a,l
	cp	e
	ret

delrsx:
	ld	de,dir
	ld	l,10h
	ld	c,8
	call	comp
	ret	nz
	ld	l,0eh
	ld	(hl),0ffh
	ld	de,0
	ld	c,59
	jp	bdos

ilprt:
	pop	hl
	ld	a,(hl)
	inc	hl
	push	hl
	or	a
	ret	z
	ld	e,a
	ld	c,2
	call	bdos
	jp	ilprt

move:
	ld	a,(hl)
	ld	(de),a
	inc	hl
	inc	de
	dec	c
	jp	nz,move
	ret

comp:
	ld	a,(de)
	cp	(hl)
	ret	nz
	inc	de
	inc	hl
	dec	c
	jp	nz,comp
	ret

	dseg

stack	equ	100h
scbpb:	db	3ah,0
rootdir:
	db	'ROOT    '
off:	db	'OFF     '
rsx66:	db	66
dir:	db	'DIR     '
diradr:	ds	2
dirend:	ds	2
rootbuf:
	ds	128
rootdrv:
	ds	1
rootloc:
	ds	1
scbase:	ds	2


	end	setdir