1/*	$NetBSD: string.c,v 1.1 2024/02/18 20:57:50 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#include <isc/util.h>
60
61#if !defined(HAVE_STRLCPY)
62size_t
63strlcpy(char *dst, const char *src, size_t size) {
64	char *d = dst;
65	const char *s = src;
66	size_t n = size;
67
68	/* Copy as many bytes as will fit */
69	if (n != 0U && --n != 0U) {
70		do {
71			if ((*d++ = *s++) == 0) {
72				break;
73			}
74		} while (--n != 0U);
75	}
76
77	/* Not enough room in dst, add NUL and traverse rest of src */
78	if (n == 0U) {
79		if (size != 0U) {
80			*d = '\0'; /* NUL-terminate dst */
81		}
82		while (*s++) {
83		}
84	}
85
86	return (s - src - 1); /* count does not include NUL */
87}
88#endif /* !defined(HAVE_STRLCPY) */
89
90#if !defined(HAVE_STRLCAT)
91size_t
92strlcat(char *dst, const char *src, size_t size) {
93	char *d = dst;
94	const char *s = src;
95	size_t n = size;
96	size_t dlen;
97
98	/* Find the end of dst and adjust bytes left but don't go past end */
99	while (n-- != 0U && *d != '\0') {
100		d++;
101	}
102	dlen = d - dst;
103	n = size - dlen;
104
105	if (n == 0U) {
106		return (dlen + strlen(s));
107	}
108	while (*s != '\0') {
109		if (n != 1U) {
110			*d++ = *s;
111			n--;
112		}
113		s++;
114	}
115	*d = '\0';
116
117	return (dlen + (s - src)); /* count does not include NUL */
118}
119#endif /* !defined(HAVE_STRLCAT) */
120
121#if !defined(HAVE_STRNSTR)
122char *
123strnstr(const char *s, const char *find, size_t slen) {
124	char c, sc, *r;
125	size_t len;
126
127	if ((c = *find++) != '\0') {
128		len = strlen(find);
129		do {
130			do {
131				if (slen-- < 1 || (sc = *s++) == '\0')
132					return (NULL);
133			} while (sc != c);
134			if (len > slen)
135				return (NULL);
136		} while (strncmp(s, find, len) != 0);
137		s--;
138	}
139	DE_CONST(s, r);
140	return (r);
141}
142#endif
143
144int
145isc_string_strerror_r(int errnum, char *buf, size_t buflen) {
146#if defined(_WIN32) || defined(_WIN64)
147	return (strerror_s(buf, buflen, errnum));
148#else  /* if defined(_WIN32) || defined(_WIN64) */
149	return (strerror_r(errnum, buf, buflen));
150#endif /* if defined(_WIN32) || defined(_WIN64) */
151}
152