illumos-port-bash/lib/sh/strcasestr.c

47 lines
1.4 KiB
C

/* strcasestr.c - Find if one string appears as a substring of another string,
without regard to case. */
/* Copyright (C) 2000 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne Again SHell.
Bash is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Bash is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Bash. If not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <bashansi.h>
#include <chartypes.h>
#include <stdc.h>
/* Determine if s2 occurs in s1. If so, return a pointer to the
match in s1. The compare is case insensitive. This is a
case-insensitive strstr(3). */
char *
strcasestr (s1, s2)
const char *s1;
const char *s2;
{
register int i, l, len, c;
c = TOLOWER ((unsigned char)s2[0]);
len = strlen (s1);
l = strlen (s2);
for (i = 0; (len - i) >= l; i++)
if ((TOLOWER ((unsigned char)s1[i]) == c) && (strncasecmp (s1 + i, s2, l) == 0))
return ((char *)s1 + i);
return ((char *)0);
}