.import _ltoa, _ultoa
.import _strlower, _strlen
.import jmpvec
- .importzp sp, ptr1, ptr2, tmp1, regbank, sreg
+ .importzp sp, ptr1, tmp1, regbank, sreg
.macpack generic
; We will store variables into the register bank in the zeropage. Define
; equates for these variables.
-ArgList = regbank+0 ; Argument list pointer
-Format = regbank+2 ; Format string
-OutData = regbank+4 ; Function parameters
+ArgList = regbank+0 ; Argument list pointer
+Format = regbank+2 ; Format string
+OutData = regbank+4 ; Function parameters
+
+; ----------------------------------------------------------------------------
+; Other zero page cells
+
+Base = ptr1
.code
ldx #>CharArg
jsr pushax
jsr push1
- jmp (OutFunc) ; fout (OutData, &CharArg, 1)
+ jmp (OutFunc) ; fout (OutData, &CharArg, 1)
; ----------------------------------------------------------------------------
; Decrement the argument list pointer by 2
rts
; ----------------------------------------------------------------------------
-; Add the a new digit in X to the value in ptr1. Does leave Y alone.
+; Read an integer from the format string. Will return zero in Y.
-AddDigit:
- txa ; Move digit into A
+ReadInt:
+ ldy #0
+ sty ptr1
+ sty ptr1+1 ; Start with zero
+@Loop: lda (Format),y ; Get format string character
sub #'0' ; Make number from ascii digit
- pha
- lda ptr1
- ldx ptr1+1
- asl ptr1
- rol ptr1+1 ; * 2
- asl ptr1
- rol ptr1+1 ; * 4
- add ptr1
- sta ptr1
- txa
- adc ptr1+1
- sta ptr1+1 ; * 5
- asl ptr1
- rol ptr1+1 ; * 10
- pla
- add ptr1 ; Add digit value
- sta ptr1
- bcc @L1
- inc ptr1+1
-@L1: rts
+ bcc @L9 ; Jump if done
+ cmp #9+1
+ bcs @L9 ; Jump if done
-; ----------------------------------------------------------------------------
-; Read an integer from the format string. Will return zero in Y.
+; Skip the digit character
-ReadInt:
- ldy #0
- sty ptr1
- sty ptr1+1 ; Start with zero
-@L1: lda (Format),y ; Get format string character
- tax ; Format character --> X
- lda __ctype,x ; Get character classification
- and #$04 ; Digit?
- beq @L9 ; Jump if done
- jsr AddDigit ; Add the digit to ptr1
- jsr IncFormatPtr ; Skip the character
- jmp @L1
+ jsr IncFormatPtr
+
+; Add the digit to the value we have in ptr1
+
+ pha ; Save digit value
+ lda ptr1
+ ldx ptr1+1
+ asl ptr1
+ rol ptr1+1 ; * 2
+ asl ptr1
+ rol ptr1+1 ; * 4, assume carry clear
+ adc ptr1
+ sta ptr1
+ txa
+ adc ptr1+1
+ sta ptr1+1 ; * 5
+ asl ptr1
+ rol ptr1+1 ; * 10, assume carry clear
+ pla
+ adc ptr1 ; Add digit value
+ sta ptr1
+ bcc @Loop
+ inc ptr1+1
+ bcs @Loop ; Branch always
+
+; We're done converting
@L9: lda ptr1
- ldx ptr1+1 ; Load result
+ ldx ptr1+1 ; Load result
rts
+
; ----------------------------------------------------------------------------
; Put a character into the argument buffer and increment the buffer index
rts
; ----------------------------------------------------------------------------
-; Get a pointer to the current buffer end
+; Get a pointer to the current buffer end and push it onto the stack
-GetBufPtr:
- lda #<Buf
- ldx #>Buf
- add BufIdx
- bcc @L1
- inx
-@L1: rts
+PushBufPtr:
+ lda #<Buf
+ ldx #>Buf
+ add BufIdx
+ bcc @L1
+ inx
+@L1: jmp pushax
; ----------------------------------------------------------------------------
; Push OutData onto the software stack
jsr pushax
jmp (OutFunc)
+; ----------------------------------------------------------------------------
+; ltoa: Wrapper for _ltoa that pushes all arguments
+
+ltoa: sty Base ; Save base
+ jsr pusheax ; Push value
+ jsr PushBufPtr ; Push the buffer pointer...
+ lda Base ; Restore base
+ jmp _ltoa ; ultoa (l, s, base);
+
+
+; ----------------------------------------------------------------------------
+; ultoa: Wrapper for _ultoa that pushes all arguments
+
+ultoa: sty Base ; Save base
+ jsr pusheax ; Push value
+ jsr PushBufPtr ; Push the buffer pointer...
+ lda Base ; Restore base
+ jmp _ultoa ; ultoa (l, s, base);
+
+
; ----------------------------------------------------------------------------
;
dex
bpl @L1
-; Start with reading the flags if there are any
-
- ldx #$FF ; "true" flag
+; Start with reading the flags if there are any. X is $FF which is used
+; for "true"
ReadFlags:
lda (Format),y ; Get next char...
; It is a character
jsr GetIntArg ; Get the argument (promoted to int)
- jsr PutBuf
- lda #0 ; Place it as zero terminated string...
- jsr PutBuf ; ...into the buffer
+ sta Buf ; Place it as zero terminated string...
+ lda #0
+ sta Buf+1 ; ...into the buffer
jmp HaveArg ; Done
; Is it an integer?
sty Buf
inc BufIdx
-@Int1: jsr pusheax
- jsr GetBufPtr
- jsr pushax
- lda #10
- jsr _ltoa ; ltoa (va_arg (ap, long), s, 10);
+@Int1: ldy #10 ; Base
+ jsr ltoa ; Push arguments, call _ltoa
jmp HaveArg
; Is it a count pseudo format?
jsr GetSignedArg ; Get argument as a long
ldy AltForm ; Alternative form?
beq @Oct1 ; Jump if no
- tay ; Save low byte of value
+ pha ; Save low byte of value
stx tmp1
ora tmp1
ora sreg
ora Prec+1 ; Check if value or Prec != 0
beq @Oct1
lda #'0'
- sta Buf
- inc BufIdx
- tya ; Restore low byte
+ jsr PutBuf
+ pla ; Restore low byte
-@Oct1: jsr pusheax ; Push value
- jsr GetBufPtr ; Get buffer pointer...
- jsr pushax ; ...and push it
- lda #8 ; Load base
- jsr _ltoa ; ltoa (l, s, 8);
+@Oct1: ldy #8 ; Load base
+ jsr ltoa ; Push arguments, call _ltoa
jmp HaveArg
; Check for a string specifier (%s)
; It's an unsigned integer
jsr GetUnsignedArg ; Get argument as unsigned long
- jsr pusheax
- jsr GetBufPtr ; Get buffer pointer...
- jsr pushax ; ...and push it
- lda #10 ; Load base
- jsr _ultoa ; ultoa (l, s, 10);
+ ldy #10 ; Load base
+ jsr ultoa ; Push arguments, call _ultoa
jmp HaveArg
; Check for a hexadecimal integer (%x)
lda #'X'
jsr PutBuf
-@L1: jsr GetUnsignedArg ; Get argument as an unsigned long
- jsr pusheax
- jsr GetBufPtr ; Get buffer pointer...
- jsr pushax ; ...and push it
- lda #16 ; Load base
- jsr _ultoa ; ultoa (l, s, 16);
+@L1: jsr GetUnsignedArg ; Get argument as an unsigned long
+ ldy #16 ; Load base
+ jsr ultoa ; Push arguments, call _ultoa
pla ; Get the format spec
cmp #'x' ; Lower case?
RegSave: .res 6
; Stuff from OutData. Is used as a vector and must be aligned
-.align 2
OutFunc: .word 0
; One character argument for OutFunc
projects / cc65 / commitdiff