;
; peekpoke.asm -- peek and poke functions for Eco-C88 which function
; like those in the Datalight library instead of those in the
; Ecosoft library.
;

Include amodel.h
Include c:\headers\pro.h

If BIGCODE
	ARG	Equ	6		; offset of first argument
else
	ARG	Equ	4
endif

; put the code in $b$prog even though it is big code
; to save segments

$b$prog	Segment	'code'

;
; peekbuf -- peek and return in buffer.  Peek at the location
; specified by segment seg and offset off for numbytes bytes.
; Place the data found in the buffer pointed to by buf.
;
; The C declration would look like:
;
;	void peekbuf(seg, off, buf, numbytes)
;	int seg, off, numbytes;
;	char *buf;
;

	Public	_peekbuf
If	BIGCODE
_peekbuf	Proc	Far
else
_peekbuf	Proc	Near
endif

	PUSH	BP
	MOV	BP,SP
	PUSH	DS
	PUSH	ES
	MOV	DS,[BP][ARG]		; source segment
	MOV	SI,[BP][ARG+2]		; source pointer in DS:SI
If	BIGDATA
	LES	DI,[BP][ARG+4]		; get pointer to buf in ES:DI
	MOV	CX,[BP][ARG+8]
else
	MOV	AX,SS
	MOV	ES,AX
	MOV	DI,[BP][ARG+4]		; get pointer to buf in ES:DI
	MOV	CX,[BP][ARG+6]		; get byte count
endif

	SHR	CX,1		; convert bytes to words
	JZ	mla		; jump if no full words to move
REP	MOVSW			; move the words
mla:	JNC	mlfin		; no bytes to move
	MOVSB			; move the left over byte
mlfin:

	POP	ES			; restore es
	POP	DS			; restore ds
	POP	BP
	RET
_peekbuf	EndP


;
; pokebuf -- poke from buffer into memory.  Poke the contents of
; buf into memory at the location specified by segment seg and
; offset off for numbytes bytes.
;
; The C declaration would look like:
;
;	void pokebuf(seg, off, buf, numbytes)
;	int seg, off, numbytes;
;	char *buf;
;

	Public	_pokebuf
If	BIGCODE
_pokebuf	Proc	Far
else
_pokebuf	Proc	Near
endif

	PUSH	BP
	MOV	BP,SP

If	BIGDATA
	PUSH	DS
	MOV	ES,[BP][ARG]	;segment of destination
	MOV	DI,[BP][ARG+2]	;ES:DI -> destination
	LDS	SI,[BP][ARG+4]	;DS:SI -> buf (source pointer)
	MOV	CX,[BP][ARG+8]	;# of bytes to move
else
	PUSH	ES
	MOV	ES,[BP][ARG]	;segment of destination
	MOV	DI,[BP][ARG+2]	;offset of destination
	MOV	SI,[BP][ARG+4]	;buf (source offset)
	MOV	CX,[BP][ARG+6]	;# of bytes to move
endif

	SHR	CX,1		; convert bytes to words
	JZ	mlb		; jump if no full words to move
REP	MOVSW			; move the words
mlb:	JNC	mldone		; no bytes to move
	MOVSB			; move the left over byte
mldone:

If	BIGDATA
	POP	DS
else
	POP	ES
endif

	POP	BP
	RET
_pokebuf	EndP

$b$prog	EndS
	End