strlcpy.c 1.5 KB

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  1. /*
  2. * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
  3. *
  4. * Permission to use, copy, modify, and distribute this software for any
  5. * purpose with or without fee is hereby granted, provided that the above
  6. * copyright notice and this permission notice appear in all copies.
  7. *
  8. * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  9. * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10. * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11. * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12. * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13. * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14. * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15. */
  16. #include <string.h>
  17. #include <sys/types.h>
  18. /*
  19. * Copy src to string dst of size siz. At most siz-1 characters
  20. * will be copied. Always NUL terminates (unless siz == 0).
  21. * Returns strlen(src); if retval >= siz, truncation occurred.
  22. */
  23. size_t
  24. strlcpy(char *dst, const char *src, size_t siz)
  25. {
  26. char *d = dst;
  27. const char *s = src;
  28. size_t n = siz;
  29. /* Copy as many bytes as will fit */
  30. if (n != 0) {
  31. while (--n != 0) {
  32. if ((*d++ = *s++) == '\0')
  33. break;
  34. }
  35. }
  36. /* Not enough room in dst, add NUL and traverse rest of src */
  37. if (n == 0) {
  38. if (siz != 0)
  39. *d = '\0'; /* NUL-terminate dst */
  40. while (*s++)
  41. ;
  42. }
  43. return(s - src - 1); /* count does not include NUL */
  44. }