release/src/router/mysql/strings/strnlen.c

   1 /* Copyright (c) 2000, 2001, 2007 MySQL AB
   2    Use is subject to license terms.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; version 2 of the License.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12
  13    You should have received a copy of the GNU General Public License
  14    along with this program; if not, write to the Free Software
  15    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
  16 */
  17
  18 /*  File   : strnlen.c
  19     Author : Michael Widenius
  20     Updated: 20 April 1984
  21     Defines: strnlen.
  22     strnlen(s, len) returns the length of s or len if s is longer than len.
  23 */
  24
  25 #include <my_global.h>
  26 #include "m_string.h"
  27
  28 #ifndef HAVE_STRNLEN
  29
  30 size_t strnlen(register const char *s, register size_t maxlen)
  31 {
  32   const char *end= (const char *)memchr(s, '\0', maxlen);
  33   return end ? (size_t) (end - s) : maxlen;
  34 }
  35
  36 #endif