strncpy.c 1.1 KB

12345678910111213141516171819202122232425262728293031323334
  1. /* Copyright (C) 1991-2019 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. The GNU C Library is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU Lesser General Public
  5. License as published by the Free Software Foundation; either
  6. version 2.1 of the License, or (at your option) any later version.
  7. The GNU C Library is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10. Lesser General Public License for more details.
  11. You should have received a copy of the GNU Lesser General Public
  12. License along with the GNU C Library; if not, see
  13. <http://www.gnu.org/licenses/>. */
  14. #include <string.h>
  15. #undef strncpy
  16. #ifndef STRNCPY
  17. #define STRNCPY strncpy
  18. #endif
  19. char *
  20. STRNCPY (char *s1, const char *s2, size_t n)
  21. {
  22. size_t size = __strnlen (s2, n);
  23. if (size != n)
  24. memset (s1 + size, '\0', n - size);
  25. return memcpy (s1, s2, size);
  26. }
  27. libc_hidden_builtin_def (strncpy)