lib/strnlen.c

   1 /* Find the length of STRING, but scan at most MAXLEN characters.
   2    Copyright (C) 2005-2007, 2009-2017 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 2, 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 }