strnlen.c 1.1 KB

12345678910111213141516171819202122232425262728293031
  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. 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; either version 3, or (at your option)
  7. any later version.
  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. You should have received a copy of the GNU General Public License
  13. along with this program; if not, see <http://www.gnu.org/licenses/>. */
  14. #include <config.h>
  15. #include <string.h>
  16. /* Find the length of STRING, but scan at most MAXLEN characters.
  17. If no '\0' terminator is found in that many characters, return MAXLEN. */
  18. size_t
  19. strnlen (const char *string, size_t maxlen)
  20. {
  21. const char *end = memchr (string, '\0', maxlen);
  22. return end ? (size_t) (end - string) : maxlen;
  23. }