mirror of
https://github.com/hsoft/collapseos.git
synced 2024-12-27 03:28:08 +11:00
f9ae5ca46b
It always reads in the scratchpad with the same max size. No need for DE-dancing anymore.
129 lines
2.4 KiB
NASM
129 lines
2.4 KiB
NASM
; *** Consts ***
|
|
.equ SCRATCHPAD_SIZE 0x20
|
|
; *** Variables ***
|
|
scratchpad:
|
|
.fill SCRATCHPAD_SIZE
|
|
|
|
; *** Code ***
|
|
|
|
; Sets Z is A is ';', CR, LF, or null.
|
|
isLineEndOrComment:
|
|
cp ';'
|
|
ret z
|
|
; Continues onto isLineEnd...
|
|
|
|
; Sets Z is A is CR, LF, or null.
|
|
isLineEnd:
|
|
or a ; same as cp 0
|
|
ret z
|
|
cp 0x0d
|
|
ret z
|
|
cp 0x0a
|
|
ret
|
|
|
|
; Sets Z is A is ' ' '\t' or ','
|
|
isSep:
|
|
cp ' '
|
|
ret z
|
|
cp 0x09
|
|
ret z
|
|
cp ','
|
|
ret
|
|
|
|
; Sets Z is A is ' ', ',', ';', CR, LF, or null.
|
|
isSepOrLineEnd:
|
|
call isSep
|
|
ret z
|
|
call isLineEndOrComment
|
|
ret
|
|
|
|
; read word in (HL) and put it in (scratchpad), null terminated, for a maximum
|
|
; of SCRATCHPAD_SIZE-1 characters. As a result, A is the read length. HL is
|
|
; advanced to the next separator char.
|
|
readWord:
|
|
push bc
|
|
push de
|
|
ld de, scratchpad
|
|
ld b, SCRATCHPAD_SIZE-1
|
|
.loop:
|
|
ld a, (hl)
|
|
call isSepOrLineEnd
|
|
jr z, .success
|
|
call JUMP_UPCASE
|
|
ld (de), a
|
|
inc hl
|
|
inc de
|
|
djnz .loop
|
|
.success:
|
|
xor a
|
|
ld (de), a
|
|
ld a, SCRATCHPAD_SIZE-1
|
|
sub a, b
|
|
.end:
|
|
pop de
|
|
pop bc
|
|
ret
|
|
|
|
; (HL) being a string, advance it to the next non-sep character.
|
|
; Set Z if we could do it before the line ended, reset Z if we couldn't.
|
|
toWord:
|
|
.loop:
|
|
ld a, (hl)
|
|
call isLineEndOrComment
|
|
jr z, .error
|
|
call isSep
|
|
jr nz, .success
|
|
inc hl
|
|
jr .loop
|
|
.error:
|
|
call JUMP_UNSETZ
|
|
ret
|
|
.success:
|
|
xor a ; ensure Z
|
|
ret
|
|
|
|
; Advance HL to the beginning of the next line, that is, right after the next
|
|
; 0x10 or 0x13 or both. If we reach null, we stop and error out.
|
|
; Sets Z on success, unsets it on error.
|
|
gotoNextLine:
|
|
dec hl ; a bit weird, but makes the looping easier
|
|
.loop:
|
|
inc hl
|
|
ld a, (hl)
|
|
call isLineEnd
|
|
jr nz, .loop
|
|
; (HL) is 0x10, 0x13 or 0
|
|
or a ; is 0?
|
|
jr z, .error
|
|
; we might have 0x13 followed by 0x10, let's account for this.
|
|
; Yes, 0x10 followed by 0x10 will make us skip two lines, but this is of
|
|
; no real consequence in our context.
|
|
inc hl
|
|
ld a, (hl)
|
|
call isLineEnd
|
|
jr nz, .success
|
|
or a ; is 0?
|
|
jr z, .error
|
|
; There was another line sep. Skip this char
|
|
inc hl
|
|
; Continue on to .success
|
|
.success:
|
|
xor a ; ensure Z
|
|
ret
|
|
.error:
|
|
call JUMP_UNSETZ
|
|
ret
|
|
|
|
; Repeatedly calls gotoNextLine until the line in (HL) points to a line that
|
|
; isn't blank or 100% comment. Sets Z if we reach a line, Unset Z if we reach
|
|
; EOF
|
|
gotoNextNotBlankLine:
|
|
call toWord
|
|
ret z ; Z set? we have a not-blank line
|
|
; Z not set? (HL) is at the end of the line or at the beginning of
|
|
; comments.
|
|
call gotoNextLine
|
|
ret nz
|
|
jr gotoNextNotBlankLine
|
|
|