1/* strindex.c - Find if one string appears as a substring of another string,
2		without regard to case. */
3
4/* Copyright (C) 2000 Free Software Foundation, Inc.
5
6   This file is part of GNU Bash, the Bourne Again SHell.
7
8   Bash is free software: you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation, either version 3 of the License, or
11   (at your option) any later version.
12
13   Bash is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16   GNU General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with Bash.  If not, see <http://www.gnu.org/licenses/>.
20*/
21
22#include <config.h>
23
24#include <bashansi.h>
25#include <chartypes.h>
26
27#include <stdc.h>
28
29/* Determine if s2 occurs in s1.  If so, return a pointer to the
30   match in s1.  The compare is case insensitive.  This is a
31   case-insensitive strstr(3). */
32char *
33strindex (s1, s2)
34     const char *s1;
35     const char *s2;
36{
37  register int i, l, len, c;
38
39  c = TOLOWER ((unsigned char)s2[0]);
40  len = strlen (s1);
41  l = strlen (s2);
42  for (i = 0; (len - i) >= l; i++)
43    if ((TOLOWER ((unsigned char)s1[i]) == c) && (strncasecmp (s1 + i, s2, l) == 0))
44      return ((char *)s1 + i);
45  return ((char *)0);
46}
47