1/*	$NetBSD: string.c,v 1.8 2024/02/21 22:52:29 christos Exp $	*/
2
3/*
4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5 *
6 * SPDX-License-Identifier: MPL-2.0
7 *
8 * This Source Code Form is subject to the terms of the Mozilla Public
9 * License, v. 2.0. If a copy of the MPL was not distributed with this
10 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11 *
12 * See the COPYRIGHT file distributed with this work for additional
13 * information regarding copyright ownership.
14 */
15
16/*
17 * SPDX-License-Identifier: BSD-3-Clause
18 *
19 * Copyright (c) 2001 Mike Barcroft <mike@FreeBSD.org>
20 * Copyright (c) 1990, 1993
21 *	The Regents of the University of California.  All rights reserved.
22 *
23 * This code is derived from software contributed to Berkeley by
24 * Chris Torek.
25 *
26 * Redistribution and use in source and binary forms, with or without
27 * modification, are permitted provided that the following conditions
28 * are met:
29 * 1. Redistributions of source code must retain the above copyright
30 *    notice, this list of conditions and the following disclaimer.
31 * 2. Redistributions in binary form must reproduce the above copyright
32 *    notice, this list of conditions and the following disclaimer in the
33 *    documentation and/or other materials provided with the distribution.
34 * 3. Neither the name of the University nor the names of its contributors
35 *    may be used to endorse or promote products derived from this software
36 *    without specific prior written permission.
37 *
38 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
39 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
41 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
42 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
43 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
44 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
45 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
46 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
47 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48 * SUCH DAMAGE.
49 */
50
51/*! \file */
52
53#ifdef _GNU_SOURCE
54#undef _GNU_SOURCE
55#endif /* ifdef _GNU_SOURCE */
56#include <string.h>
57
58#include <isc/string.h> /* IWYU pragma: keep */
59
60#if !defined(HAVE_STRLCPY)
61size_t
62strlcpy(char *dst, const char *src, size_t size) {
63	char *d = dst;
64	const char *s = src;
65	size_t n = size;
66
67	/* Copy as many bytes as will fit */
68	if (n != 0U && --n != 0U) {
69		do {
70			if ((*d++ = *s++) == 0) {
71				break;
72			}
73		} while (--n != 0U);
74	}
75
76	/* Not enough room in dst, add NUL and traverse rest of src */
77	if (n == 0U) {
78		if (size != 0U) {
79			*d = '\0'; /* NUL-terminate dst */
80		}
81		while (*s++) {
82		}
83	}
84
85	return (s - src - 1); /* count does not include NUL */
86}
87#endif /* !defined(HAVE_STRLCPY) */
88
89#if !defined(HAVE_STRLCAT)
90size_t
91strlcat(char *dst, const char *src, size_t size) {
92	char *d = dst;
93	const char *s = src;
94	size_t n = size;
95	size_t dlen;
96
97	/* Find the end of dst and adjust bytes left but don't go past end */
98	while (n-- != 0U && *d != '\0') {
99		d++;
100	}
101	dlen = d - dst;
102	n = size - dlen;
103
104	if (n == 0U) {
105		return (dlen + strlen(s));
106	}
107	while (*s != '\0') {
108		if (n != 1U) {
109			*d++ = *s;
110			n--;
111		}
112		s++;
113	}
114	*d = '\0';
115
116	return (dlen + (s - src)); /* count does not include NUL */
117}
118#endif /* !defined(HAVE_STRLCAT) */
119
120#if !defined(HAVE_STRNSTR)
121char *
122strnstr(const char *s, const char *find, size_t slen) {
123	char c, sc;
124	size_t len;
125
126	if ((c = *find++) != '\0') {
127		len = strlen(find);
128		do {
129			do {
130				if (slen-- < 1 || (sc = *s++) == '\0')
131					return (NULL);
132			} while (sc != c);
133			if (len > slen)
134				return (NULL);
135		} while (strncmp(s, find, len) != 0);
136		s--;
137	}
138	return ((char *)s);
139}
140#endif
141
142int
143isc_string_strerror_r(int errnum, char *buf, size_t buflen) {
144	return (strerror_r(errnum, buf, buflen));
145}
146