1 /*-------------------------------------------------------------------------
2 *
3 * strlcpy.c
4 * strncpy done right
5 *
6 * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
7 *
8 *
9 * IDENTIFICATION
10 * src/port/strlcpy.c
11 *
12 * This file was taken from OpenBSD and is used on platforms that don't
13 * provide strlcpy(). The OpenBSD copyright terms follow.
14 *-------------------------------------------------------------------------
15 */
16
17 /* $OpenBSD: strlcpy.c,v 1.11 2006/05/05 15:27:38 millert Exp $ */
18
19 /*
20 * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
21 *
22 * Permission to use, copy, modify, and distribute this software for any
23 * purpose with or without fee is hereby granted, provided that the above
24 * copyright notice and this permission notice appear in all copies.
25 *
26 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
27 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
28 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
29 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
30 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
31 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
32 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
33 */
34
35 #include "c.h"
36
37
38 /*
39 * Copy src to string dst of size siz. At most siz-1 characters
40 * will be copied. Always NUL terminates (unless siz == 0).
41 * Returns strlen(src); if retval >= siz, truncation occurred.
42 * Function creation history: http://www.gratisoft.us/todd/papers/strlcpy.html
43 */
44 size_t
strlcpy(char * dst,const char * src,size_t siz)45 strlcpy(char *dst, const char *src, size_t siz)
46 {
47 char *d = dst;
48 const char *s = src;
49 size_t n = siz;
50
51 /* Copy as many bytes as will fit */
52 if (n != 0)
53 {
54 while (--n != 0)
55 {
56 if ((*d++ = *s++) == '\0')
57 break;
58 }
59 }
60
61 /* Not enough room in dst, add NUL and traverse rest of src */
62 if (n == 0)
63 {
64 if (siz != 0)
65 *d = '\0'; /* NUL-terminate dst */
66 while (*s++)
67 ;
68 }
69
70 return (s - src - 1); /* count does not include NUL */
71 }
72