/*-

 * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG>

 * All rights reserved.

 *

 * 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.

 *

 * 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/strcspn.c,v 1.5 2005/04/02 18:52:44 das Exp $");

#endif

#include <sys/types.h>

#include <limits.h>

#include <string.h>

#define	IDX(c)	((u_char)(c) / LONG_BIT)

#define	BIT(c)	((u_long)1 << ((u_char)(c) % LONG_BIT))

EXPORT_C 

size_t

strcspn(const char *s, const char *charset)

{

	/*

	 * NB: idx and bit are temporaries whose use causes gcc 3.4.2 to

	 * generate better code.  Without them, gcc gets a little confused.

	 */

	const char *s1;

	u_long bit;

	u_long tbl[(UCHAR_MAX + 1) / LONG_BIT];

	int idx;

	if(*s == '\0')

		return (0);

#if LONG_BIT == 64	/* always better to unroll on 64-bit architectures */

	tbl[0] = 1;

	tbl[3] = tbl[2] = tbl[1] = 0;

#else

	for (tbl[0] = idx = 1; idx < sizeof(tbl) / sizeof(tbl[0]); idx++)

		tbl[idx] = 0;

#endif

	for (; *charset != '\0'; charset++) {

		idx = IDX(*charset);

		bit = BIT(*charset);

		tbl[idx] |= bit;

	}

	for(s1 = s; ; s1++) {

		idx = IDX(*s1);

		bit = BIT(*s1);

		if ((tbl[idx] & bit) != 0)

			break;

	}

	return (s1 - s);

}