strlcat.c 1.9 KB

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  1. /* OPENBSD ORIGINAL: lib/libc/string/strlcat.c */
  2. /* $OpenBSD: strlcat.c,v 1.11 2003/06/17 21:56:24 millert Exp $ */
  3. /*
  4. * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
  5. *
  6. * Permission to use, copy, modify, and distribute this software for any
  7. * purpose with or without fee is hereby granted, provided that the above
  8. * copyright notice and this permission notice appear in all copies.
  9. *
  10. * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11. * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12. * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13. * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14. * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15. * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16. * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17. */
  18. #include "common.h"
  19. #ifndef HAVE_STRLCAT
  20. #if defined(LIBC_SCCS) && !defined(lint)
  21. static char *rcsid = "$OpenBSD: strlcat.c,v 1.11 2003/06/17 21:56:24 millert Exp $";
  22. #endif /* LIBC_SCCS and not lint */
  23. #include <sys/types.h>
  24. #include <string.h>
  25. /*
  26. * Appends src to string dst of size siz (unlike strncat, siz is the
  27. * full size of dst, not space left). At most siz-1 characters
  28. * will be copied. Always NUL terminates (unless siz <= strlen(dst)).
  29. * Returns strlen(src) + MIN(siz, strlen(initial dst)).
  30. * If retval >= siz, truncation occurred.
  31. */
  32. size_t
  33. strlcat(char *dst, const char *src, size_t siz)
  34. {
  35. register char *d = dst;
  36. register const char *s = src;
  37. register size_t n = siz;
  38. size_t dlen;
  39. /* Find the end of dst and adjust bytes left but don't go past end */
  40. while (n-- != 0 && *d != '\0')
  41. d++;
  42. dlen = d - dst;
  43. n = siz - dlen;
  44. if (n == 0)
  45. return(dlen + strlen(s));
  46. while (*s != '\0') {
  47. if (n != 1) {
  48. *d++ = *s;
  49. n--;
  50. }
  51. s++;
  52. }
  53. *d = '\0';
  54. return(dlen + (s - src)); /* count does not include NUL */
  55. }
  56. #endif /* !HAVE_STRLCAT */