mirror of
https://github.com/cc65/cc65.git
synced 2024-11-04 17:04:58 +00:00
104 lines
2.3 KiB
ArmAsm
104 lines
2.3 KiB
ArmAsm
;
|
|
; Christian Groessler, 10.02.2009
|
|
; derived from strncmp.s and stricmp.s
|
|
;
|
|
; int __fastcall__ strnicmp (const char* s1, const char* s2, size_t count);
|
|
; int __fastcall__ strncasecmp (const char* s1, const char* s2, size_t count);
|
|
;
|
|
|
|
.export _strnicmp, _strncasecmp
|
|
.import popax, __ctype
|
|
.importzp ptr1, ptr2, ptr3, tmp1
|
|
|
|
.include "ctype.inc"
|
|
|
|
_strnicmp:
|
|
_strncasecmp:
|
|
|
|
; Convert the given counter value in a/x from a downward counter into an
|
|
; upward counter, so we can increment the counter in the loop below instead
|
|
; of decrementing it. This adds some overhead now, but is cheaper than
|
|
; executing a more complex test in each iteration of the loop. We do also
|
|
; correct the value by one, so we can do the test on top of the loop.
|
|
|
|
eor #$FF
|
|
sta ptr3
|
|
txa
|
|
eor #$FF
|
|
sta ptr3+1
|
|
|
|
; Get the remaining arguments
|
|
|
|
jsr popax ; get s2
|
|
sta ptr2
|
|
stx ptr2+1
|
|
jsr popax ; get s1
|
|
sta ptr1
|
|
stx ptr1+1
|
|
|
|
; Loop setup
|
|
|
|
ldy #0
|
|
|
|
; Start of compare loop. Check the counter.
|
|
|
|
Loop: inc ptr3
|
|
beq IncHi ; Increment high byte
|
|
|
|
; Compare a byte from the strings
|
|
|
|
Comp: lda (ptr2),y
|
|
tax
|
|
lda __ctype,x ; get character classification
|
|
and #CT_LOWER ; lower case char?
|
|
beq L1 ; jump if no
|
|
txa ; get character back
|
|
sec
|
|
sbc #<('a'-'A') ; make upper case char
|
|
tax ;
|
|
L1: stx tmp1 ; remember upper case equivalent
|
|
|
|
lda (ptr1),y ; get character from first string
|
|
tax
|
|
lda __ctype,x ; get character classification
|
|
and #CT_LOWER ; lower case char?
|
|
beq L2 ; jump if no
|
|
txa ; get character back
|
|
sec
|
|
sbc #<('a'-'A') ; make upper case char
|
|
tax
|
|
|
|
L2: cpx tmp1 ; compare characters
|
|
bne NotEqual ; Jump if strings different
|
|
txa ; End of strings?
|
|
beq Equal1 ; Jump if EOS reached, a/x == 0
|
|
|
|
; Increment the pointers
|
|
|
|
iny
|
|
bne Loop
|
|
inc ptr1+1
|
|
inc ptr2+1
|
|
bne Loop ; Branch always
|
|
|
|
; Increment hi byte
|
|
|
|
IncHi: inc ptr3+1
|
|
bne Comp ; Jump if counter not zero
|
|
|
|
; Exit code if strings are equal. a/x not set
|
|
|
|
Equal: lda #$00
|
|
tax
|
|
Equal1: rts
|
|
|
|
; Exit code if strings not equal
|
|
|
|
NotEqual:
|
|
bcs L3
|
|
ldx #$FF ; Make result negative
|
|
rts
|
|
|
|
L3: ldx #$01 ; Make result positive
|
|
rts
|