/**
 * vim: set ts=4 sw=4 tw=99 et :
 * =============================================================================
 * SourceMod
 * Copyright (C) 2004-2009 AlliedModders LLC.  All rights reserved.
 * =============================================================================
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, version 3.0, as published by the
 * Free Software Foundation.
 * 
 * This program 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
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * As a special exception, AlliedModders LLC gives you permission to link the
 * code of this program (as well as its derivative works) to "Half-Life 2," the
 * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
 * by the Valve Corporation.  You must obey the GNU General Public License in
 * all respects for all other code used.  Additionally, AlliedModders LLC grants
 * this exception to all derivative works.  AlliedModders LLC defines further
 * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
 * or <http://www.sourcemod.net/license.php>.
 *
 * Version: $Id$
 */

#include <string.h>
#include <ctype.h>
#include "stringutil.h"

const char *stristr(const char *str, const char *substr)
{
	if (!*substr)
	{
		return ((char *)str);
	}

	char *needle = (char *)substr;
	char *prevloc = (char *)str;
	char *haystack = (char *)str;

	while (*haystack)
	{
		if (tolower(*haystack) == tolower(*needle))
		{
			haystack++;
			if (!*++needle)
			{
				return prevloc;
			}
		}
		else
		{
			haystack = ++prevloc;
			needle = (char *)substr;
		}
	}

	return NULL;
}