1/*	$NetBSD: strl_obsd.c,v 1.5 2020/05/25 20:47:24 christos Exp $	*/
2
3/*
4 * Why use strlcpy()/strlcat() instead of standard strncpy()/strncat()?
5 * To reduce likelihood of bugs and avoid wasteful zero fills.  See:
6 * http://www.gratisoft.us/todd/papers/strlcpy.html
7 */
8
9/*	$OpenBSD: strlcpy.c,v 1.11 2006/05/05 15:27:38 millert Exp $	*/
10
11/*
12 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
13 *
14 * Permission to use, copy, modify, and distribute this software for any
15 * purpose with or without fee is hereby granted, provided that the above
16 * copyright notice and this permission notice appear in all copies.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
19 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
20 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
21 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
22 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
23 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
24 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
25 */
26
27#include <config.h>		/* + marks local changes */
28#ifdef HAVE_SYS_TYPES_H		/* + */
29#include <sys/types.h>
30#endif				/* + */
31#include <string.h>
32
33#include "ntp_stdlib.h"		/* + strlcpy, strlcat prototypes */
34
35#ifndef HAVE_STRLCPY		/* + */
36/*
37 * Copy src to string dst of size siz.  At most siz-1 characters
38 * will be copied.  Always NUL terminates (unless siz == 0).
39 * Returns strlen(src); if retval >= siz, truncation occurred.
40 */
41size_t
42strlcpy(char *dst, const char *src, size_t siz)
43{
44	char *d = dst;
45	const char *s = src;
46	size_t n = siz;
47
48	/* Copy as many bytes as will fit */
49	if (n != 0) {
50		while (--n != 0) {
51			if ((*d++ = *s++) == '\0')
52				break;
53		}
54	}
55
56	/* Not enough room in dst, add NUL and traverse rest of src */
57	if (n == 0) {
58		if (siz != 0)
59			*d = '\0';		/* NUL-terminate dst */
60		while (*s++)
61			;
62	}
63
64	return(s - src - 1);	/* count does not include NUL */
65}
66#endif				/* + */
67
68
69/*	$OpenBSD: strlcat.c,v 1.13 2005/08/08 08:05:37 espie Exp $	*/
70
71/*
72 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
73 *
74 * Permission to use, copy, modify, and distribute this software for any
75 * purpose with or without fee is hereby granted, provided that the above
76 * copyright notice and this permission notice appear in all copies.
77 *
78 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
79 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
80 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
81 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
82 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
83 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
84 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
85 */
86
87/* #include <sys/types.h> */	/* + */
88/* #include <string.h> */	/* + */
89
90#ifndef HAVE_STRLCAT		/* + */
91/*
92 * Appends src to string dst of size siz (unlike strncat, siz is the
93 * full size of dst, not space left).  At most siz-1 characters
94 * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
95 * Returns strlen(src) + MIN(siz, strlen(initial dst)).
96 * If retval >= siz, truncation occurred.
97 */
98size_t
99strlcat(char *dst, const char *src, size_t siz)
100{
101	char *d = dst;
102	const char *s = src;
103	size_t n = siz;
104	size_t dlen;
105
106	/* Find the end of dst and adjust bytes left but don't go past end */
107	while (n-- != 0 && *d != '\0')
108		d++;
109	dlen = d - dst;
110	n = siz - dlen;
111
112	if (n == 0)
113		return(dlen + strlen(s));
114	while (*s != '\0') {
115		if (n != 1) {
116			*d++ = *s;
117			n--;
118		}
119		s++;
120	}
121	*d = '\0';
122
123	return(dlen + (s - src));	/* count does not include NUL */
124}
125#endif				/* + */
126