strlcpy.c (1620B)
1/* $OpenBSD: strlcpy.c,v 1.12 2015/01/15 03:54:12 millert Exp $ */
23
/*
4* Copyright (c) 1998, 2015 Todd C. Miller <Todd.Miller@courtesan.com>
5*
6* Permission to use, copy, modify, and distribute this software for any
7* purpose with or without fee is hereby granted, provided that the above
8* copyright notice and this permission notice appear in all copies.
9*
10* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17*/
1819
#include <sys/types.h>
20#include <string.h>
2122
#include "compat.h"
2324
/*
25* Copy string src to buffer dst of size dsize. At most dsize-1
26* chars will be copied. Always NUL terminates (unless dsize == 0).
27* Returns strlen(src); if retval >= dsize, truncation occurred.
28*/
29size_t
30strlcpy(char *dst, const char *src, size_t dsize)
31{
32const char *osrc = src;
33size_t nleft = dsize;
3435
/* Copy as many bytes as will fit. */
36if (nleft != 0) {
37while (--nleft != 0) {
38if ((*dst++ = *src++) == '\0')
39break;
40}
41}
4243
/* Not enough room in dst, add NUL and traverse rest of src. */
44if (nleft == 0) {
45if (dsize != 0)
46*dst = '\0'; /* NUL-terminate dst */
47while (*src++)
48;
49}
5051
return(src - osrc - 1); /* count does not include NUL */
52}