openssh-portable/match.c

79 lines
1.9 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 1.1 1999/10/27 03:42:44 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)
{
while (1)
{
/* If at end of pattern, accept if also at end of string. */
if (!*pattern)
return !*s;
/* Process '*'. */
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*/
}