; Program:	SAVESTAMP for Z80DOS systems.
; Author:	Carson Wilson
; Assembly:	Z80ASM, PDLN, SYSLIB
; Date: 	September 26, 1987
; Version:	1.0
;
; Purpose:	Copies create date from one file to another under Z80DOS.
;
; Usage:	By using SAVESTAMP, the creation date of modified files
;		can be preserved after using an editor or other program which
;		renames the original file to filename.BAK.
;
; Syntax:
;
;	SAVESTMP or SAVESTMP /					- Display help.
;	SAVESTMP [du: or dir:]dest.fil [du: or dir:]source.fil	- ZCPR usage
;	SAVESTMP [d:]dest.fil [d:]source.fil			- CP/M usage
;

bdos	equ	5
bell	equ	7
tab	equ	9
cr	equ	0dh
lf	equ	0ah
fcb1	equ	5ch
fcb2	equ	6ch
defDMA	equ	80h
dmastp	equ	0e0h	; Stamp indicator in DMA after search
bwrite	equ	14	; BIOS write block call with SYSLIB
seldsk	equ	14	; BDOS select disk
sfirst	equ	17
user	equ	32	; BDOS set/get user
GetStp	equ	54	; Z80DOS function call
user1	equ	69h	; ZCPR user # for fcb1
user2	equ	79h

vers	equ	10

	.request SYSLIB

	external moveb,bios,print,pfn2

begin:
	jp	start
	db	'Z3ENV'
	db	3
envaddr:
	dw	00000h		; Environment address
	dw	begin
start:
	call	print
	db	cr,lf,'SAVESTAMP: ',0	; sign-on
	ld	a,(defdma)
	or	a
	jr	z,help		; No input?
	ld	a,(fcb1+1)	; Get 1st char. after possible spaces
	cp	'/'		; Help?
	jp	nz,copystmp	; No
	ld	a,(fcb1+2)
	cp	' '		; Next char. non-blank?
	jp	nz,copystmp	; Yes
;
; Display help
;
help:
	call	print
	db	'Version ',vers/10+'0','.',vers	mod 10+'0','.'
	db	tab,'Copies Z80DOS file create date.',cr,lf
	db	' Syntax:',cr,lf
	db	tab,'SAVESTMP [du: or dir:]dest.fil [du: or dir:]source.fil'
	db	tab,'- ZCPR usage',cr,lf
	db	tab,'SAVESTMP [d:]dest.fil [d:]source.fil'
	db	tab,tab,tab,'- CP/M usage',cr,lf,0
	ret
;
; Copy create date, if any
;
copystmp:
	ld	hl,(envaddr)	; Get environment address
	ld	a,h		; Test if running under Z3
	or	l
	ld	(z3flg),a	; Zero if not ZCPR environment
				; ..non-zero if ZCPR
	jr	z,getsrc	; Don't set user
;
; Search for source file
;
	ld	a,(user2)	; Get ZCPR source user
	ld	e,a
	ld	c,user
	call	bdos		; Select source user
getsrc:
	ld	de,fcb2
	push	de		; Save for error message
	ld	c,sfirst	; Search for first
	call	bdos
	pop	de		; Retrieve file name
	inc	a
	jp	z,missing	; A = 0ffh --> 0 = error
;
	ld	c,getstp	; Z80DOS call
	call	bdos		; HL --> file's stamp if any
	ld	de,stamp	; Point to buffer for source stamp
	ld	b,2
	call	moveb		; SYSLIB copy 2 byte stamp to buffer
;
; Search for dest. file
;
	ld	a,(z3flg)	; ZCPR?
	or	a
	jr	z,getdest	; No, don't select user
	ld	a,(user1)	; Get ZCPR dest. user
	ld	e,a
	ld	c,user
	call	bdos		; Select dest. user
getdest:
	ld	de,fcb1
	push	de		; For error message
	ld	c,sfirst	; Load BIOS dirbuf with dir. sector
	call	bdos
	pop	de
	inc	a
	jp	z,missing	; 0ffh --> 0 = dest. file not found
;
	dec	a		; Save directory return code
	push	af
;
; Got both files, now test destination for stamps
;
	ld	a,(dmastp)	; Test time stamps on dest.
	cp	'!'
	jr	z,stamps	; Stamps found
	pop	af
	jp	nostamps	; Not found, abort
;
; Stamps exist on destination, so copy stamp
;
stamps:
	call	print
	db	'Altering creation date of ',0
	ld	de,fcb1+1
	call	pfn2
	call	print
	db	' . . . ',0
;
; First select disk, if necessary
;
	ld	a,(fcb1)	; Dest. file's disk
	or	a		; Default disk?
	jr	z,copy		; Yes, so don't select disk
	dec	a		; 0 = A for SelDsk
	ld	e,a		; Non-default disk
	ld	c,seldsk	; Select disk so that BIOS sector
	call	bdos		; ..write goes to right disk!
copy:
	pop	af		; Retrieve dir. search code
	ld	e,a		; (A = 0, 1, or 2)
	sla	a		; Multiply by 10
	sla	a
	add	a,e
	sla	a
	add	a,2		; A = offset to create date (2,12,22)
	ld	e,a		; Save in E
	xor	a
	ld	d,a		; Zero D
	ld	hl,dmastp	; Dir. stamp location in DMA buffer
	add	hl,de
	ex	de,hl		; DE --> Dest file's create stamp

	ld	hl,stamp	; Point to buffer holding source stamp
	ld	b,2
	call	moveb		; SYSLIB copy 2 bytes from buffer to DMA

	ld	c,1		; Force directory sector write of DMA
	ld	a,bwrite	; BIOS write sector
	call	bios
	or	a		; BIOS return code: A = 0 --> okay
	jp	nz,badwrite
	call	print		; Write ok
	db	'Done.',cr,lf,0
	ret			; Done
;
; Error Routines
;
nostamps:
	call	print
	db	bell,'No time stamps present on destination disk!'
	db	cr,lf,0
	ret
;
missing:
	inc	de
	call	pfn2		; SYSLIB print file name
	call	print
	db	' not found.',cr,lf,bell,0
	ret
;
badwrite:
	call	print
	db	bell,'Write error!',cr,lf,0
	ret
;
; Data area
;
	dseg

z3flg:
	ds	1		; ZCPR environment
stamp:
	ds	2		; Save date stamp

	end

; END SAVESTMP.Z80