;
;	NAME:  SVLIN.M68
;
	OBJNAM	.SBR
;
;	FUNCTION:  This subroutine is used to read data from a SuperVue file
;	one line at a time. Since SuperVue does not terminate its data line 
;	with a CR+LF pair, SVLIN reads the data until it finds a CR then
;	returns the data in the BUFFER string
;       If LENGTH returned = 0 then and end of file is reached
;       If your Supervue file contains the header information used in SuperVUE
;	it can be found by checking for CHR$(1) which is the begining
;       of the header information and CHR$(1) which is the terminating 
;	character for the header information on the first line input
;
;	CALLING SEQUENCE:  XCALL SVLIN,OPTION,AREA{,BUFFER|NAME{,LENGTH}}
;	where
;	Name	Type	Use
;	OPTION	Float	1=open
;			2=read
;			3=close
;	AREA	X,616	DDB and buffer
;	BUFFER	Any	Returned data (READ call) make sure it is large
;		        enough to accept a whole line of data
;	NAME	String	Filename (OPEN call)
;	LENGTH	Float	Length of returned data (READ call)
;
;	AUTHOR: James A. Jarboe of this version GR/AM
;       VERY VERY LARGELY taken from FILEIN.M68 by Tom Dahlquist
;       donated to AMUS
;
;	EDIT HISTORY:
;	  When   Who What
;	          Tom dahlquist wrote it as FILEIN.M68
;	11/15/85 JAJ modified for Supervue file input
;
;MAP1	OPTION,F,6	! 1=open  2=read 3=close
;MAP1	AREA,X,616	! DDB area do not change
;MAP1	BUFFER,S,200	! make sure size is compatable with line length of
;			! file read
;MAP1	FILE$,S,24,"TEST.T"	! filename
;MAP1	LENGTH,F		! length of line returned here
;
;! open file
;	OPTION=1
;	? "Opening ";FILE$
;	XCALL SVLIN,OPTION,AREA,FILE$
;	OPTION=2
;ONE:
;	
;        ? "Reading ";FILE$
;	CALL IN			! get sv line
;        IF BUFFER[1,1]#CHR$(1) &
;		THEN GOTO FIRST'LINE   ! check for sv header info
;
;HEADTST:
;	HEAD=INSTR(2,BUFFER,CHR$(1))	! check for end of header info
;	BUFFER=BUFFER[HEAD+1,LENGTH]	! take out header info
;	LENGTH=LENGTH-HEAD		! make LENGTH =  -header data
;FIRST'LINE:
;	GOTO PRINTIT			! print it out to screen or file
;
;PROCESS:	
; 	CALL IN				! get next line
;	IF LENGTH=0 THEN GOTO LOSE	! if end of file then close it
;PRINTIT:
; 	? BUFFER;		!print buffer
;	? CHR$(10);		!print a line feed
; 	GOTO PROCESS
;
;!!!!!!!!!!!!
;! SUBROUTINES
;!!!!!!!!!!!!
;
;IN:
;	BUFFER=""		! clear buffer
;	OPTION=2		! read option
;	XCALL SVLIN,OPTION,AREA,BUFFER,LENGTH
;	RETURN		
;LOSE:
;	FILE$="TEST.T"
;	OPTION=3		! close option
;	? "CLOSING ";FILE$
;	XCALL SVLIN,OPTION,AREA,FILE$
;	END

	SEARCH	SYS
	SEARCH	SYSSYM

	ASECT
	.=0
PRMCNT:	BLKW	1
TYPE1:	BLKW	1			; type of arg 1
ADDR1:	BLKL	1			; address of arg1
SIZE1:	BLKL	1			; size arg1
TYPE2:	BLKW	1
ADDR2:	BLKL	1
SIZE2:	BLKL	1
TYPE3:	BLKW	1
ADDR3:	BLKL	1
SIZE3:	BLKL	1
TYPE4:	BLKW	1
ADDR4:	BLKL	1
SIZE4:	BLKL	1

	PSECT
	.=0
	VMAJOR=1
	VMINOR=1
	VEDIT=0

SVLIN:	PHDR	-1,0,PH$REU!PH$REE
	CMPW	@A3,#3			; must be at least 3 args...
	BLO	RETURN			; back if not...
	MOVW	TYPE1(A3),D6		; get type of first...
	ANDW	#7,D6			; must be float...
	CMPW	D6,#4			; back if not...
	BNE	RETURN
	CMP	SIZE2(A3),#616.		; right size?
	BNE	RETURN			; back if not.
	MOV	ADDR1(A3),A0		; get option...
	FFTOL	@A0,D0			; D1=option...
	MOV	ADDR2(A3),A0		; A0->DDB...
	CMPW	D0,#1			; OPEN...
	BEQ	OPEN
	CMPW	D0,#2			; READ...
	BEQ	READ
	CMPW	D0,#3			; CLOSE
	JEQ	CLOSE
RETURN:	RTN
;
;	OPEN--clear the DDB, initialize it, open file.
;
OPEN:	CLEAR	@A0,D.DDB		; clear it...
	LEA	A6,D.DDB(A0)		; A6->I/O buffer...
	MOV	A6,D.BUF(A0)		; put into DDB...
	MOVB	#D$INI,D.FLG(A0)	; set INITed...
	MOV	ADDR3(A3),A2		; A2->filename...
	FSPEC	@A0,T  			; put filename into DDB, and
	OPENI	@A0			; open it.
	RTN
;	
;	READ--move bytes to buffer until a CR, or file is empty.
;
READ:	CMPW	@A3,#4			; must have fourth arg...
	BLO	RETURN
	MOVW	TYPE4(A3),D6		; check type of it...
	ANDW	#7,D6
	CMPW	D6,#4
	BNE	RETURN
	MOV	ADDR3(A3),A1		; A1->buffer...
 	MOV	SIZE3(A3),D0		; D0=length of buffer...
 	DEC	D0			; minus 1 for DBF...   
 	CLR	D2			; D2 used as counter...
LOOP:	FILINB	@A0			; ask for next byte...
	TST	D.SIZ(A0)		; anything left?
	BEQ	EOF			; br if not...
 	MOVB	D1,(A1)+		; move it in...
 	ADDW	#1,D2			; increment counter...
	CMPB	D1,#13.			; is it end of a SuperVUE line?
	BEQ	EOF			; well then lets get ready to go
 	DBF	D0,LOOP			; and loop.
 	BR	SETLTH
EOF:	CLRB	(A1)+			; clear rest of buffer...
 	DBF	D0,EOF                  ; was out
SETLTH:	MOV	ADDR4(A3),A1		; A1->length variable...
	FLTOF	D2,@A1			; convert length...
	RTN
;
;	CLOSE--close the file.
;
CLOSE:	CLOSE	@A0
	RTN

	END

.