mirror of
https://github.com/cc65/cc65.git
synced 2024-11-05 08:05:51 +00:00
43 lines
1.2 KiB
ArmAsm
43 lines
1.2 KiB
ArmAsm
;
|
|
; 1998-06-02, Ullrich von Bassewitz
|
|
; 2013-08-28, Greg King
|
|
;
|
|
; char* __fastcall__ strlower (char* s);
|
|
; char* __fastcall__ strlwr (char* s);
|
|
;
|
|
; Non-ANSI
|
|
;
|
|
|
|
.export _strlower, _strlwr
|
|
.import popax
|
|
.importzp ptr1, ptr2
|
|
.import ctypemaskdirect
|
|
.include "ctype.inc"
|
|
|
|
_strlower:
|
|
_strlwr:
|
|
sta ptr1 ; save s (working copy)
|
|
stx ptr1+1
|
|
sta ptr2
|
|
stx ptr2+1 ; save function result
|
|
ldy #0
|
|
|
|
loop: lda (ptr1),y ; get character
|
|
beq L9 ; jump if done
|
|
jsr ctypemaskdirect ; get character classification
|
|
and #CT_UPPER ; upper case char?
|
|
beq L1 ; jump if no
|
|
lda (ptr1),y ; fetch character again
|
|
adc #<('a'-'A') ; make lower case char (ctypemaskdirect ensures carry clear)
|
|
sta (ptr1),y ; store back
|
|
L1: iny ; next char
|
|
bne loop
|
|
inc ptr1+1 ; handle offset overflow
|
|
bne loop ; branch always
|
|
|
|
; Done, return the argument string
|
|
|
|
L9: lda ptr2
|
|
ldx ptr2+1
|
|
rts
|