gonzui: t2ex/bsd_source/lib/libc/src

    1: /*      $OpenBSD: strncat.c,v 1.5 2005/08/08 08:05:37 espie Exp $ */
    2: /*-
    3:  * Copyright (c) 1990 The Regents of the University of California.
    4:  * All rights reserved.
    5:  *
    6:  * This code is derived from software contributed to Berkeley by
    7:  * Chris Torek.
    8:  *
    9:  * Redistribution and use in source and binary forms, with or without
   10:  * modification, are permitted provided that the following conditions
   11:  * are met:
   12:  * 1. Redistributions of source code must retain the above copyright
   13:  *    notice, this list of conditions and the following disclaimer.
   14:  * 2. Redistributions in binary form must reproduce the above copyright
   15:  *    notice, this list of conditions and the following disclaimer in the
   16:  *    documentation and/or other materials provided with the distribution.
   17:  * 3. Neither the name of the University nor the names of its contributors
   18:  *    may be used to endorse or promote products derived from this software
   19:  *    without specific prior written permission.
   20:  *
   21:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   22:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   23:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   24:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   25:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   26:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   27:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   28:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   29:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   30:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   31:  * SUCH DAMAGE.
   32:  */
   33: 
   34: #include <string.h>
   35: 
   36: /*
   37:  * Concatenate src on the end of dst.  At most strlen(dst)+n+1 bytes
   38:  * are written at dst (at most n+1 bytes being appended).  Return dst.
   39:  */
   40: char *
   41: strncat(char *dst, const char *src, size_t n)
   42: {
   43:         if (n != 0) {
   44:                 char *d = dst;
   45:                 const char *s = src;
   46: 
   47:                 while (*d != 0)
   48:                         d++;
   49:                 do {
   50:                         if ((*d = *s++) == 0)
   51:                                 break;
   52:                         d++;
   53:                 } while (--n != 0);
   54:                 *d = 0;
   55:         }
   56:         return (dst);
   57: }