1  /* Find the length of STRING, but scan at most MAXLEN characters.
       2     Copyright (C) 2005-2007, 2009-2021 Free Software Foundation, Inc.
       3     Written by Simon Josefsson.
       4  
       5     This program is free software; you can redistribute it and/or modify
       6     it under the terms of the GNU General Public License as published by
       7     the Free Software Foundation; either version 3, or (at your option)
       8     any later version.
       9  
      10     This program is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13     GNU General Public License for more details.
      14  
      15     You should have received a copy of the GNU General Public License
      16     along with this program; if not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <config.h>
      19  
      20  #include <string.h>
      21  
      22  /* Find the length of STRING, but scan at most MAXLEN characters.
      23     If no '\0' terminator is found in that many characters, return MAXLEN.  */
      24  
      25  size_t
      26  strnlen (const char *string, size_t maxlen)
      27  {
      28    const char *end = memchr (string, '\0', maxlen);
      29    return end ? (size_t) (end - string) : maxlen;
      30  }