mirror of
https://github.com/RevCurtisP/C02.git
synced 2024-11-17 15:06:29 +00:00
84 lines
3.4 KiB
Plaintext
84 lines
3.4 KiB
Plaintext
|
;Wildcard String Match Function for C02
|
||
|
|
|
||
|
|
|
||
|
|
;C02 Wrapper for Pattern Matcher Routine
|
||
|
|
;Args: X,Y = Pointer to Pattern String
|
||
|
|
;Requires: DSTLO,DSTHI = pointer to null-terminated String
|
||
|
|
;Calls: SETSRC, PTTRN
|
||
|
|
;Returns: A=$FF if match
|
||
|
|
|
||
|
|
;Match passed string against pattern pointed to by src
|
||
|
|
STRPTN: JSR SETSRC ;Initialize source string variables
|
||
|
|
JSR PTTRN ;Do pattern match
|
||
|
|
BMI STRPTM ;If string length exceeded
|
||
|
|
BCS STRPTX ;or no match found
|
||
|
|
STRPTM: INX ; Change X from $FF to $00
|
||
|
|
STRPTX: TXA ;Set Result to TRUE or FALSE
|
||
|
|
RTS ;and Return
|
||
|
|
|
||
|
|
;Pattern Matcher by Paul Guertin, 30 August 2000
|
||
|
|
;from http://6502.org/source/strings/patmatch.htm
|
||
|
|
;
|
||
|
|
;Modifications by Curtis F Kaylor, 23 May 2017
|
||
|
|
;changed labels to conform to c02 library standards
|
||
|
|
;moved index storage to memory to allow indirect reference to pattern
|
||
|
|
;added exit with N=1 if strings exceed 128 characters
|
||
|
|
;
|
||
|
|
;Requires: SRCLO,SRCHI = pointer to null-terminated Pattern
|
||
|
|
; DSTLO,DSTHI = pointer to null-terminated String
|
||
|
|
;Sets: X - $FF
|
||
|
|
; TEMP0 - index into pattern
|
||
|
|
; TEMP1 - index into string
|
||
|
|
;Uses: 4 bytes of stack for each '*' in pattern
|
||
|
|
;Affects: A,Y,Z
|
||
|
|
;Returns: C - 1 if String matches Pattern, otherwise 0
|
||
|
|
; N - 1 if String or Pattern longer than 127 characters, otherwise 0
|
||
|
|
|
||
|
|
PTTRNQ EQU "?" ;Question mark Matches exactly 1 character
|
||
|
|
PTTRNA EQU "*" ;Matches any number of characters (including 0)
|
||
|
|
|
||
|
|
PTTRN: LDX #$00 ;Initialize pattern pointer to 0
|
||
|
|
STX TEMP0
|
||
|
|
DEX ;Initialize string pointer to 255
|
||
|
|
STX TEMP1
|
||
|
|
PTTRNL: LDY TEMP0
|
||
|
|
LDA (SRCLO),Y ;Get next pattern character
|
||
|
|
CMP #PTTRNA ;If it's a '*'
|
||
|
|
BEQ PTTRNS ; Jump to star match
|
||
|
|
INC TEMP1 ;Else point to next string character
|
||
|
|
LDY TEMP1
|
||
|
|
CMP #PTTRNQ ;If it's a '?'
|
||
|
|
BNE PTTRNR ; Replace with string character
|
||
|
|
LDA (DSTLO),Y ; If End of String
|
||
|
|
BEQ PTTRNX ; Exit with no match found
|
||
|
|
PTTRNR: CMP (DSTLO),Y ;If pattern character <> string character
|
||
|
|
BNE PTTRNX ; Exit with no match found
|
||
|
|
INC TEMP0 ;Else point to next pattern character
|
||
|
|
BMI PTTRNX ;If max length exceeded, exit no match
|
||
|
|
CMP #0 ;If not string terminator
|
||
|
|
BNE PTTRNL ; Check loop
|
||
|
|
PTTRNF: RTS ;Else exit with match found
|
||
|
|
|
||
|
|
PTTRNS: INC TEMP0 ;Skip '*' in pattern
|
||
|
|
LDY TEMP0
|
||
|
|
CMP (SRCLO),Y ;If next pattern character is '*'
|
||
|
|
BEQ PTTRNS ; loop back to skip
|
||
|
|
PTTRNT: LDA TEMP0 ;Push pointer into pattern
|
||
|
|
PHA ; onto stack
|
||
|
|
LDA TEMP1 ;Push pointer into string
|
||
|
|
PHA ; onto stack
|
||
|
|
JSR PTTRNL ;Recursive call to match rest of string
|
||
|
|
PLA ;Pop pointer into string
|
||
|
|
STA TEMP1 ; off of stack
|
||
|
|
PLA ;Pop pointer into pattern
|
||
|
|
STA TEMP0 ; off of stack
|
||
|
|
BCS PTTRNF ;If rest of string matched, exit with match
|
||
|
|
INC TEMP1 ;Skip next string character
|
||
|
|
BMI PTTRNX ;If max length not exceeded
|
||
|
|
LDY TEMP1
|
||
|
|
LDA (DSTLO),Y ;and not string terminator terminator
|
||
|
|
BNE PTTRNT ; loop to pattern check
|
||
|
|
PTTRNX: CLC ;Clear carry
|
||
|
|
RTS ; and return
|
||
|
|
|