1
0
mirror of https://github.com/RevCurtisP/C02.git synced 2024-11-29 01:49:19 +00:00
C02/include/argget.a02
2021-09-25 15:28:49 -04:00

38 lines
1.6 KiB
Plaintext

;Module ARGS generic ARGGET routinr
;argget(s) - Read Next Argument into String s
;Args: X,Y - Address of String
;Uses: SYSBFR - System Buffer
; SYSBFL - System Buffer Length
;Sets: DSTPTR - Address of String
;Updates: SYSBFP - System Buffer Position
;Returns: A,Y = Argument Length
; X = New System Buffer Position
ARGGET: JSR SETDST ;Set Destination Pointer
LDY #0 ;Initialize Destination Index
LDX SYSBFP ;Get System Buffer Position
.GLOOP: LDA SYSBFR,X ;Get Next Character
BEQ .GDONE ;If String Terminator
CMP #ARGTRM ;or Argument Terminator
BEQ .GDONE ; Terminate String and Return
CMP #ARGDLM ;Else If Argument Delimiter
BNE .GSKIP ;
INX ; Bump Buffer Index Past Delimiter
CPY #0 ; If Leading Space
BEQ .GLOOP ; Check Next Character
BNE .GDONE ; Terminate String and Returns
.GSKIP LDA SYSBFR,X ;Else Get Character from Buffer
AND #ARGMSK ; Apply Bit Mask
STA (DSTPTR),Y ; Copy to Destination String
INY ; Increment Destination Index
BMI .GDONE ; If > 128, Return as Length
INX ; Increment Buffer Index
CPX #SYSBFL ; If Less Than Buffer Length
BCC .GLOOP ; Loop
.GDONE LDA #0 ;
STA (DSTPTR),Y ;Terminate Destination String
.GRTRN STX SYSBFP ;Set System Buffer Position
TYA ;Return Argument Length
RTS