gonzui

    1: /*      $OpenBSD: strncpy.c,v 1.6 2005/08/08 08:05:37 espie Exp $    */
    2: 
    3: /*-
    4:  * Copyright (c) 1990 The Regents of the University of California.
    5:  * All rights reserved.
    6:  *
    7:  * This code is derived from software contributed to Berkeley by
    8:  * Chris Torek.
    9:  *
   10:  * Redistribution and use in source and binary forms, with or without
   11:  * modification, are permitted provided that the following conditions
   12:  * are met:
   13:  * 1. Redistributions of source code must retain the above copyright
   14:  *    notice, this list of conditions and the following disclaimer.
   15:  * 2. Redistributions in binary form must reproduce the above copyright
   16:  *    notice, this list of conditions and the following disclaimer in the
   17:  *    documentation and/or other materials provided with the distribution.
   18:  * 3. Neither the name of the University nor the names of its contributors
   19:  *    may be used to endorse or promote products derived from this software
   20:  *    without specific prior written permission.
   21:  *
   22:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   23:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   24:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   25:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   26:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   27:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   28:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   29:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   30:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   31:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   32:  * SUCH DAMAGE.
   33:  */
   34: 
   35: #if !defined(_KERNEL) && !defined(_STANDALONE)
   36: #include <string.h>
   37: #else
   38: #include <lib/libkern/libkern.h>
   39: #endif
   40: 
   41: /*
   42:  * Copy src to dst, truncating or null-padding to always copy n bytes.
   43:  * Return dst.
   44:  */
   45: char *
   46: strncpy(char *dst, const char *src, size_t n)
   47: {
   48:         if (n != 0) {
   49:                 char *d = dst;
   50:                 const char *s = src;
   51: 
   52:                 do {
   53:                         if ((*d++ = *s++) == 0) {
   54:                                 /* NUL pad the remaining n-1 bytes */
   55:                                 while (--n != 0)
   56:                                         *d++ = 0;
   57:                                 break;
   58:                         }
   59:                 } while (--n != 0);
   60:         }
   61:         return (dst);
   62: }