genericopenlibs/openenvcore/libc/src/string/memmem.c
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Fri, 11 Jun 2010 15:26:22 +0300
changeset 34 5fae379060a7
parent 0 e4d67989cc36
permissions -rw-r--r--
Revision: 201023 Kit: 2010123

/*-
 * Copyright (c) 2005 Pascal Gloor <pascal.gloor@spale.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * © Portions copyright (c) 2005-2006  Nokia Corporation.  All rights reserved.
 */

#include <sys/cdefs.h>
#ifndef __SYMBIAN32__
__FBSDID("$FreeBSD: src/lib/libc/string/memmem.c,v 1.1.2.1 2005/08/29 18:46:39 andre Exp $");
#endif
#include <string.h>

/*
 * Find the first occurrence of the byte string s in byte string l.
 */
#ifdef __SYMBIAN_COMPILE_UNUSED__
void *
memmem(l, l_len, s, s_len)
	const void *l; size_t l_len;
	const void *s; size_t s_len;
{
	register char *cur, *last;
	const char *cl = (const char *)l;
	const char *cs = (const char *)s;

	/* we need something to compare */
	if (l_len == 0 || s_len == 0)
		return NULL;

	/* "s" must be smaller or equal to "l" */
	if (l_len < s_len)
		return NULL;

	/* special case where s_len == 1 */
	if (s_len == 1)
		return memchr(l, (int)*cs, l_len);

	/* the last position where its possible to find "s" in "l" */
	last = (char *)cl + l_len - s_len;

	for (cur = (char *)cl; cur <= last; cur++)
		if (cur[0] == cs[0] && memcmp(cur, cs, s_len) == 0)
			return cur;

	return NULL;
}
#endif