xref: /netbsd-src/external/mpl/bind/dist/lib/isc/string.c (revision a04395531661c5e8d314125d5ae77d4cbedd5d73)
1 /*	$NetBSD: string.c,v 1.5 2021/02/19 16:42:19 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * This Source Code Form is subject to the terms of the Mozilla Public
7  * License, v. 2.0. If a copy of the MPL was not distributed with this
8  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
9  *
10  * See the COPYRIGHT file distributed with this work for additional
11  * information regarding copyright ownership.
12  */
13 
14 /*
15  * Copyright (c) 1990, 1993
16  *	The Regents of the University of California.  All rights reserved.
17  *
18  * Redistribution and use in source and binary forms, with or without
19  * modification, are permitted provided that the following conditions
20  * are met:
21  * 1. Redistributions of source code must retain the above copyright
22  *    notice, this list of conditions and the following disclaimer.
23  * 2. Redistributions in binary form must reproduce the above copyright
24  *    notice, this list of conditions and the following disclaimer in the
25  *    documentation and/or other materials provided with the distribution.
26  * 3. Neither the name of the University nor the names of its contributors
27  *    may be used to endorse or promote products derived from this software
28  *    without specific prior written permission.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40  * SUCH DAMAGE.
41  */
42 
43 /*! \file */
44 
45 #ifdef _GNU_SOURCE
46 #undef _GNU_SOURCE
47 #endif /* ifdef _GNU_SOURCE */
48 #include <string.h>
49 
50 #include <isc/string.h> /* IWYU pragma: keep */
51 
52 #if !defined(HAVE_STRLCPY)
53 size_t
54 strlcpy(char *dst, const char *src, size_t size) {
55 	char *d = dst;
56 	const char *s = src;
57 	size_t n = size;
58 
59 	/* Copy as many bytes as will fit */
60 	if (n != 0U && --n != 0U) {
61 		do {
62 			if ((*d++ = *s++) == 0) {
63 				break;
64 			}
65 		} while (--n != 0U);
66 	}
67 
68 	/* Not enough room in dst, add NUL and traverse rest of src */
69 	if (n == 0U) {
70 		if (size != 0U) {
71 			*d = '\0'; /* NUL-terminate dst */
72 		}
73 		while (*s++) {
74 		}
75 	}
76 
77 	return (s - src - 1); /* count does not include NUL */
78 }
79 #endif /* !defined(HAVE_STRLCPY) */
80 
81 #if !defined(HAVE_STRLCAT)
82 size_t
83 strlcat(char *dst, const char *src, size_t size) {
84 	char *d = dst;
85 	const char *s = src;
86 	size_t n = size;
87 	size_t dlen;
88 
89 	/* Find the end of dst and adjust bytes left but don't go past end */
90 	while (n-- != 0U && *d != '\0') {
91 		d++;
92 	}
93 	dlen = d - dst;
94 	n = size - dlen;
95 
96 	if (n == 0U) {
97 		return (dlen + strlen(s));
98 	}
99 	while (*s != '\0') {
100 		if (n != 1U) {
101 			*d++ = *s;
102 			n--;
103 		}
104 		s++;
105 	}
106 	*d = '\0';
107 
108 	return (dlen + (s - src)); /* count does not include NUL */
109 }
110 #endif /* !defined(HAVE_STRLCAT) */
111 
112 int
113 isc_string_strerror_r(int errnum, char *buf, size_t buflen) {
114 #if defined(_WIN32) || defined(_WIN64)
115 	return (strerror_s(buf, buflen, errnum));
116 #else  /* if defined(_WIN32) || defined(_WIN64) */
117 	return (strerror_r(errnum, buf, buflen));
118 #endif /* if defined(_WIN32) || defined(_WIN64) */
119 }
120