string/strndup.c

   1 /* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 # include "config.h"
  21 #endif
  22
  23 #include <stdio.h>
  24 #include <sys/types.h>
  25
  26 #if defined _LIBC || defined STDC_HEADERS
  27 # include <stdlib.h>
  28 # include <string.h>
  29 #else
  30 char *malloc ();
  31 #endif
  32
  33 #undef __strndup
  34 #undef strndup
  35
  36 #ifndef weak_alias
  37 # define __strndup strndup
  38 #endif
  39
  40 char *
  41 __strndup (s, n)
  42      const char *s;
  43      size_t n;
  44 {
  45   size_t len = strnlen (s, n);
  46   char *new = malloc (len + 1);
  47
  48   if (new == NULL)
  49     return NULL;
  50
  51   new[len] = '\0';
  52   return memcpy (new, s, len);
  53 }
  54 #ifdef weak_alias
  55 weak_alias (__strndup, strndup)
  56 #endif