lib/libc/string/stpncpy.c

   1 /*      $NetBSD: stpncpy.c,v 1.2 2013/11/06 21:05:27 tron Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2009 David Schultz <das@FreeBSD.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 __RCSID("$NetBSD: stpncpy.c,v 1.2 2013/11/06 21:05:27 tron Exp $");
  32 #endif /* LIBC_SCCS and not lint */
  33 /* FreeBSD: src/lib/libc/string/stpncpy.c,v 1.1 2009/02/28 06:00:58 das Exp */
  34
  35 #include <string.h>
  36
  37 #ifdef _FORTIFY_SOURCE
  38 #undef stpncpy
  39 #endif
  40
  41 char *
  42 stpncpy(char * __restrict dst, const char * __restrict src, size_t n)
  43 {
  44
  45         for (; n--; dst++, src++) {
  46                 if (!(*dst = *src)) {
  47                         char *ret = dst;
  48                         while (n--)
  49                                 *++dst = '\0';
  50                         return (ret);
  51                 }
  52         }
  53         return (dst);
  54 }