//
// _MATCH.CPP
//
// Source file for ArchiveLib 1.0
//
// Copyright (c) Greenleaf Software, Inc. 1994
// All Rights Reserved
//
// CONTENTS
//
// is_pattern()
// is_valid_pattern()
// matche()
// matche_after_star()
// match()
// main() (For testing, w/conditional compile)
//
// DESCRIPTION
//
// Some nice code written by J. Kercheval, in the public domain.
// This code provides us with the pattern matching functions used
// by the ALName functions. It all seems to work without any trouble
// at all.
//
// I tried to change this file as little as possible. I modified the
// name of the file, and removed BOOLEAN, TRUE, and FALSE from the
// header file. Other than that, it is just as I found it.
//
// REVISION HISTORY
//
// May 22, 1994 1.0A : First release
//
//
#include "arclib.h"
#pragma hdrstop
/*
EPSHeader
File: match.c
Author: J. Kercheval
Created: Sat, 01/05/1991 22:21:49
*/
/*
EPSRevision History
J. Kercheval Wed, 02/20/1991 22:29:01 Released to Public Domain
J. Kercheval Fri, 02/22/1991 15:29:01 fix '\' bugs (two :( of them)
J. Kercheval Sun, 03/10/1991 19:31:29 add error return to matche()
J. Kercheval Sun, 03/10/1991 20:11:11 add is_valid_pattern code
J. Kercheval Sun, 03/10/1991 20:37:11 beef up main()
J. Kercheval Tue, 03/12/1991 22:25:10 Released as V1.1 to Public Domain
J. Kercheval Thu, 03/14/1991 22:22:25 remove '\' for DOS file parsing
J. Kercheval Mon, 05/13/1991 21:49:05 ifdef full match code
J. Kercheval Mon, 01/06/1992 21:31:44 add match character defines
*/
/*
* Wildcard Pattern Matching
*/
#include "arclib.h"
#include "_match.h"
//
// The next five lines used to be in the header file
//
#ifndef BOOLEAN
#define BOOLEAN int
#define TRUE 1
#define FALSE 0
#endif
/* character defines */
#define MATCH_CHAR_SINGLE '?'
#define MATCH_CHAR_KLEENE_CLOSURE '*'
#define MATCH_CHAR_RANGE_OPEN '['
#define MATCH_CHAR_RANGE '-'
#define MATCH_CHAR_RANGE_CLOSE ']'
#define MATCH_CHAR_LITERAL '\\'
#define MATCH_CHAR_NULL '\0'
#define MATCH_CHAR_CARAT_NEGATE '^'
#define MATCH_CHAR_EXCLAMATION_NEGATE '!'
/* forward function prototypes */
int matche_after_star( register const char *pattern, register char *text);
int fast_match_after_star(register char *pattern, register char *text);
/*----------------------------------------------------------------------------
*
* Return TRUE if PATTERN has any special wildcard characters
*
---------------------------------------------------------------------------*/
BOOLEAN is_pattern( const char *p )
{
while (*p) {
switch (*p++) {
case MATCH_CHAR_SINGLE:
case MATCH_CHAR_KLEENE_CLOSURE:
case MATCH_CHAR_RANGE_OPEN:
#ifndef FILE_MATCH
case MATCH_CHAR_LITERAL:
#endif
return TRUE;
}
}
return FALSE;
}
/*----------------------------------------------------------------------------
*
* Return TRUE if PATTERN has is a well formed regular expression according
* to the above syntax
*
* error_type is a return code based on the type of pattern error. Zero is
* returned in error_type if the pattern is a valid one. error_type return
* values are as follows:
*
* PATTERN_VALID - pattern is well formed
#ifndef FILE_MATCH
* PATTERN_ESC - pattern has invalid escape ('\' at end of pattern)
#endif
* PATTERN_RANGE - [..] construct has a no end range in a '-' pair (ie [a-])
* PATTERN_CLOSE - [..] construct has no end bracket (ie [abc-g )
* PATTERN_EMPTY - [..] construct is empty (ie [])
*
---------------------------------------------------------------------------*/
BOOLEAN is_valid_pattern( const char *p, int *error_type )
{
/* init error_type */
*error_type = PATTERN_VALID;
/* loop through pattern to EOS */
while (*p) {
/* determine pattern type */
switch (*p) {
#ifndef FILE_MATCH
/* check literal escape, it cannot be at end of pattern */
case MATCH_CHAR_LITERAL:
if (!*++p) {
*error_type = PATTERN_ESC;
return FALSE;
}
p++;
break;
#endif
/* the [..] construct must be well formed */
case MATCH_CHAR_RANGE_OPEN:
p++;
/* if the next character is ']' then bad pattern */
if (*p == MATCH_CHAR_RANGE_CLOSE) {
*error_type = PATTERN_EMPTY;
return FALSE;
}
/* if end of pattern here then bad pattern */
if (!*p) {
*error_type = PATTERN_CLOSE;
return FALSE;
}
/* loop to end of [..] construct */
while (*p != MATCH_CHAR_RANGE_CLOSE) {
/* check for literal escape */
if (*p == MATCH_CHAR_LITERAL) {
p++;
/* if end of pattern here then bad pattern */
if (!*p++) {
*error_type = PATTERN_ESC;
return FALSE;
}
}
else
p++;
/* if end of pattern here then bad pattern */
if (!*p) {
*error_type = PATTERN_CLOSE;
return FALSE;
}
/* if this a range */
if (*p == MATCH_CHAR_RANGE) {
/* we must have an end of range */
if (!*++p || *p == MATCH_CHAR_RANGE_CLOSE) {
*error_type = PATTERN_RANGE;
return FALSE;
}
else {
/* check for literal escape */
if (*p == MATCH_CHAR_LITERAL)
p++;
/* if end of pattern here then bad pattern */
if (!*p++) {
*error_type = PATTERN_ESC;
return FALSE;
}
}
}
}
break;
/* all other characters are valid pattern elements */
case MATCH_CHAR_KLEENE_CLOSURE:
case MATCH_CHAR_SINGLE:
default: /* "normal" character */
p++;
break;
}
}
return TRUE;
}
/*----------------------------------------------------------------------------
*
* Match the pattern PATTERN against the string TEXT;
*
* returns MATCH_VALID if pattern matches, or an errorcode as follows
* otherwise:
*
* MATCH_PATTERN - bad pattern
#ifndef FILE_MATCH
* MATCH_LITERAL - match failure on literal mismatch
#endif
* MATCH_RANGE - match failure on [..] construct
* MATCH_ABORT - premature end of text string
* MATCH_END - premature end of pattern string
* MATCH_VALID - valid match
*
*
* A match means the entire string TEXT is used up in matching.
*
* In the pattern string:
* `*' matches any sequence of characters (zero or more)
* `?' matches any character
* [SET] matches any character in the specified set,
* [!SET] or [^SET] matches any character not in the specified set.
* \ is allowed within a set to escape a character like ']' or '-'
*
* A set is composed of characters or ranges; a range looks like character
* hyphen character (as in 0-9 or A-Z). [0-9a-zA-Z_] is the minimal set of
* characters allowed in the [..] pattern construct. Other characters are
* allowed (ie. 8 bit characters) if your system will support them.
*
* To suppress the special syntactic significance of any of `[]*?!^-\', and
* match the character exactly, precede it with a `\'.
*
---------------------------------------------------------------------------*/
int matche( const char *p, char *t)
{
register char range_start, range_end; /* start and end in range */
BOOLEAN invert; /* is this [..] or [!..] */
BOOLEAN member_match; /* have I matched the [..] construct? */
BOOLEAN loop; /* should I terminate? */
for (; *p; p++, t++) {
/* if this is the end of the text then this is the end of the match */
if (!*t) {
return (*p == MATCH_CHAR_KLEENE_CLOSURE &&
*++p == MATCH_CHAR_NULL) ?
MATCH_VALID : MATCH_ABORT;
}
/* determine and react to pattern type */
switch (*p) {
/* single any character match */
case MATCH_CHAR_SINGLE:
break;
/* multiple any character match */
case MATCH_CHAR_KLEENE_CLOSURE:
return matche_after_star(p, t);
/* [..] construct, single member/exclusion character match */
case MATCH_CHAR_RANGE_OPEN:{
/* move to beginning of range */
p++;
/* check if this is a member match or exclusion match */
invert = FALSE;
if (*p == MATCH_CHAR_EXCLAMATION_NEGATE ||
*p == MATCH_CHAR_CARAT_NEGATE) {
invert = TRUE;
p++;
}
/* if closing bracket here or at range start then we have
* a malformed pattern */
if (*p == MATCH_CHAR_RANGE_CLOSE) {
return MATCH_PATTERN;
}
member_match = FALSE;
loop = TRUE;
while (loop) {
/* if end of construct then loop is done */
if (*p == MATCH_CHAR_RANGE_CLOSE) {
loop = FALSE;
continue;
}
/* matching a '!', '^', '-', '\' or a ']' */
if (*p == MATCH_CHAR_LITERAL) {
range_start = range_end = *++p;
}
else {
range_start = range_end = *p;
}
/* if end of pattern then bad pattern (Missing ']') */
if (!*p)
return MATCH_PATTERN;
/* check for range bar */
if (*++p == MATCH_CHAR_RANGE) {
/* get the range end */
range_end = *++p;
/* if end of pattern or construct then bad
* pattern */
if (range_end == MATCH_CHAR_NULL ||
range_end == MATCH_CHAR_RANGE_CLOSE)
return MATCH_PATTERN;
/* special character range end */
if (range_end == MATCH_CHAR_LITERAL) {
range_end = *++p;
/* if end of text then we have a bad pattern */
if (!range_end)
return MATCH_PATTERN;
}
/* move just beyond this range */
p++;
}
/* if the text character is in range then match
* found. make sure the range letters have the proper
* relationship to one another before comparison */
if (range_start < range_end) {
if (*t >= range_start && *t <= range_end) {
member_match = TRUE;
loop = FALSE;
}
}
else {
if (*t >= range_end && *t <= range_start) {
member_match = TRUE;
loop = FALSE;
}
}
}
/* if there was a match in an exclusion set then no match */
/* if there was no match in a member set then no match */
if ((invert && member_match) ||
!(invert || member_match))
return MATCH_RANGE;
/* if this is not an exclusion then skip the rest of the
* [...] construct that already matched. */
if (member_match) {
while (*p != MATCH_CHAR_RANGE_CLOSE) {
/* bad pattern (Missing MATCH_CHAR_RANGE_CLOSE) */
if (!*p)
return MATCH_PATTERN;
/* skip exact match */
if (*p == MATCH_CHAR_LITERAL) {
p++;
/* if end of text then we have a bad pattern */
if (!*p)
return MATCH_PATTERN;
}
/* move to next pattern char */
p++;
}
}
break;
}
#ifndef FILE_MATCH
/* next character is quoted and must match exactly */
case MATCH_CHAR_LITERAL:
/* move pattern pointer to quoted char and fall through */
p++;
/* if end of text then we have a bad pattern */
if (!*p)
return MATCH_PATTERN;
#endif
/* must match this character exactly */
default:
if (*p != *t)
return MATCH_LITERAL;
}
}
/* if end of text not reached then the pattern fails */
if (*t)
return MATCH_END;
else
return MATCH_VALID;
}
/*----------------------------------------------------------------------------
*
* recursively call matche() with final segment of PATTERN and of TEXT.
*
---------------------------------------------------------------------------*/
int matche_after_star( register const char *p, register char *t)
{
register int match = 0;
register nextp;
/* pass over existing ? and * in pattern */
while (*p == MATCH_CHAR_SINGLE ||
*p == MATCH_CHAR_KLEENE_CLOSURE) {
/* take one char for each ? and + */
if (*p == MATCH_CHAR_SINGLE) {
/* if end of text then no match */
if (!*t++) {
return MATCH_ABORT;
}
}
/* move to next char in pattern */
p++;
}
/* if end of pattern we have matched regardless of text left */
if (!*p) {
return MATCH_VALID;
}
/* get the next character to match which must be a literal or '[' */
nextp = *p;
#ifndef FILE_MATCH
if (nextp == MATCH_CHAR_LITERAL) {
nextp = p[1];
/* if end of text then we have a bad pattern */
if (!nextp)
return MATCH_PATTERN;
}
#endif
/* Continue until we run out of text or definite result seen */
do {
/* a precondition for matching is that the next character in the
* pattern match the next character in the text or that the next
* pattern char is the beginning of a range. Increment text pointer
* as we go here */
if (nextp == *t || nextp == MATCH_CHAR_RANGE_OPEN) {
match = matche(p, t);
}
/* if the end of text is reached then no match */
if (!*t++)
match = MATCH_ABORT;
} while (match != MATCH_VALID &&
match != MATCH_ABORT &&
match != MATCH_PATTERN);
/* return result */
return match;
}
/*----------------------------------------------------------------------------
*
* match() is a shell to matche() to return only BOOLEAN values.
*
---------------------------------------------------------------------------*/
BOOLEAN match( char *p, char *t)
{
int error_type;
error_type = matche(p, t);
return (error_type == MATCH_VALID) ? TRUE : FALSE;
}
#ifdef TEST
/*
* This test main expects as first arg the pattern and as second arg
* the match string. Output is yaeh or nay on match. If nay on
* match then the error code is parsed and written.
*/
#include <stdio.h>
int main(int argc, char *argv[])
{
int error;
int is_valid_error;
if (argc != 3) {
printf("Usage: MATCH Pattern Text\n");
}
else {
printf("Pattern: %s\n", argv[1]);
printf("Text : %s\n", argv[2]);
if ( !is_pattern(argv[1])) {
printf(" First Argument Is Not A Pattern\n");
}
else {
#ifdef FILE_MATCH
match(argv[1], argv[2]) ? printf("TRUE") : printf("FALSE");
#endif
error = matche(argv[1], argv[2]);
is_valid_pattern(argv[1], &is_valid_error);
switch (error) {
case MATCH_VALID:
printf(" Match Successful");
if (is_valid_error != PATTERN_VALID)
printf(" -- is_valid_pattern() is complaining\n");
else
printf("\n");
break;
#ifndef FILE_MATCH
case MATCH_LITERAL:
printf(" Match Failed on Literal\n");
break;
#endif
case MATCH_RANGE:
printf(" Match Failed on [..]\n");
break;
case MATCH_ABORT:
printf(" Match Failed on Early Text Termination\n");
break;
case MATCH_END:
printf(" Match Failed on Early Pattern Termination\n");
break;
case MATCH_PATTERN:
switch (is_valid_error) {
case PATTERN_VALID:
printf(" Internal Disagreement On Pattern\n");
break;
#ifndef FILE_MATCH
case PATTERN_ESC:
printf(" Literal Escape at End of Pattern\n");
break;
#endif
case PATTERN_RANGE:
printf(" No End of Range in [..] Construct\n");
break;
case PATTERN_CLOSE:
printf(" [..] Construct is Open\n");
break;
case PATTERN_EMPTY:
printf(" [..] Construct is Empty\n");
break;
default:
printf(" Internal Error in is_valid_pattern()\n");
}
break;
default:
printf(" Internal Error in matche()\n");
break;
}
}
}
return (0);
}
#endif