1/*	$NetBSD: strpbrk.c,v 1.3 2024/01/20 14:55:11 christos Exp $	*/
2
3/*-
4 * Copyright (c) 2008 Joerg Sonnenberger
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__RCSID("$NetBSD: strpbrk.c,v 1.3 2024/01/20 14:55:11 christos Exp $");
30
31#if !defined(_KERNEL) && !defined(_STANDALONE)
32#include <assert.h>
33#include <inttypes.h>
34#include <limits.h>
35#include <string.h>
36#else
37#include <lib/libkern/libkern.h>
38#endif
39
40#define FAST_STRPBRK 1
41#define UC(a) ((unsigned int)(unsigned char)(a))
42
43#ifdef FAST_STRPBRK
44#define ADD_NEW_TO_SET(i) (set[inv[i] = idx++] = (i))
45#define IS_IN_SET(i) (inv[i] < idx && set[inv[i]] == (i))
46#define ADD_TO_SET(i) (void)(IS_IN_SET(i) || /*LINTED no effect*/ADD_NEW_TO_SET(i))
47#else
48#define IS_IN_SET(i) (set[(i) >> 3] & idx[(i) & 7])
49#define ADD_TO_SET(i) (void)(set[(i) >> 3] |= idx[(i) & 7])
50#endif
51
52char *
53strpbrk(const char *s, const char *charset)
54{
55#ifdef FAST_STRPBRK
56	uint8_t set[256], inv[256], idx = 0;
57#else
58	static const size_t idx[8] = { 1, 2, 4, 8, 16, 32, 64, 128 };
59	uint8_t set[32];
60
61	(void)memset(set, 0, sizeof(set));
62#endif
63
64	if (charset[0] == '\0')
65		return NULL;
66	if (charset[1] == '\0')
67		return __UNCONST(strchr(s, charset[0]));
68
69	for (; *charset != '\0'; ++charset)
70		ADD_TO_SET(UC(*charset));
71
72	for (; *s != '\0'; ++s)
73		if (IS_IN_SET(UC(*s)))
74			return __UNCONST(s);
75	return NULL;
76}
77