cosmopolitan/libc/str/strlcpy.c

43 lines
2.4 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program is distributed in the hope that it will be useful, but │
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/safemacros.internal.h"
#include "libc/str/str.h"
/**
* Copies string, the BSD way.
*
* @param d is buffer which needn't be initialized
* @param s is a NUL-terminated string
* @param n is byte capacity of d
* @return strlen(s)
* @note d and s can't overlap
* @note we prefer memccpy()
*/
size_t strlcpy(char *d, const char *s, size_t n) {
size_t slen, actual;
slen = strlen(s);
if (n) {
actual = min(n, slen);
memcpy(d, s, actual);
d[actual] = '\0';
}
return slen;
}