strnlen.c

来自「bison 2.0 主要可以用来做语法分析用的」· C语言 代码 · 共 49 行

/* Find the length of STRING, but scan at most MAXLEN characters.
   Copyright (C) 1996, 1997, 1998, 2000-2003 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   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; either version 2, or (at your option)
   any later version.

   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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#if HAVE_CONFIG_H
# include <config.h>
#endif
#undef strnlen

#include <string.h>

#undef __strnlen
#undef strnlen

#ifndef _LIBC
# define strnlen rpl_strnlen
#endif

#ifndef weak_alias
# define __strnlen strnlen
#endif

/* Find the length of STRING, but scan at most MAXLEN characters.
   If no '\0' terminator is found in that many characters, return MAXLEN.  */

size_t
__strnlen (const char *string, size_t maxlen)
{
  const char *end = memchr (string, '\0', maxlen);
  return end ? (size_t) (end - string) : maxlen;
}
#ifdef weak_alias
weak_alias (__strnlen, strnlen)
#endif