openssh-portable/match.c

83 lines
1.7 KiB
C

/*
*
* match.c
*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
*
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
*
* Created: Thu Jun 22 01:17:50 1995 ylo
*
* Simple pattern matching, with '*' and '?' as wildcards.
*
*/
#include "includes.h"
RCSID("$Id: match.c,v 1.3 1999/11/25 00:54:59 damien Exp $");
#include "ssh.h"
/*
* Returns true if the given string matches the pattern (which may contain ?
* and * as wildcards), and zero if it does not match.
*/
int
match_pattern(const char *s, const char *pattern)
{
for (;;) {
/* If at end of pattern, accept if also at end of string. */
if (!*pattern)
return !*s;
if (*pattern == '*') {
/* Skip the asterisk. */
pattern++;
/* If at end of pattern, accept immediately. */
if (!*pattern)
return 1;
/* If next character in pattern is known, optimize. */
if (*pattern != '?' && *pattern != '*') {
/*
* Look instances of the next character in
* pattern, and try to match starting from
* those.
*/
for (; *s; s++)
if (*s == *pattern &&
match_pattern(s + 1, pattern + 1))
return 1;
/* Failed. */
return 0;
}
/*
* Move ahead one character at a time and try to
* match at each position.
*/
for (; *s; s++)
if (match_pattern(s, pattern))
return 1;
/* Failed. */
return 0;
}
/*
* There must be at least one more character in the string.
* If we are at the end, fail.
*/
if (!*s)
return 0;
/* Check if the next character of the string is acceptable. */
if (*pattern != '?' && *pattern != *s)
return 0;
/* Move to the next character, both in string and in pattern. */
s++;
pattern++;
}
/* NOTREACHED */
}