strlcat.c 2.4 KB

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  1. /* $NetBSD: strlcat.c,v 1.5 1999/09/20 04:39:47 lukem Exp $ */
  2. /* from OpenBSD: strlcat.c,v 1.2 1999/06/17 16:28:58 millert Exp */
  3. /*
  4. * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
  5. * All rights reserved.
  6. *
  7. * Redistribution and use in source and binary forms, with or without
  8. * modification, are permitted provided that the following conditions
  9. * are met:
  10. * 1. Redistributions of source code must retain the above copyright
  11. * notice, this list of conditions and the following disclaimer.
  12. * 2. Redistributions in binary form must reproduce the above copyright
  13. * notice, this list of conditions and the following disclaimer in the
  14. * documentation and/or other materials provided with the distribution.
  15. * 3. The name of the author may not be used to endorse or promote products
  16. * derived from this software without specific prior written permission.
  17. *
  18. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  19. * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  20. * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  21. * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  22. * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  23. * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  24. * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  25. * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  26. * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  27. * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28. */
  29. #ifdef HAVE_CONFIG_H
  30. #include <config.h>
  31. #endif
  32. #include <netdissect-stdinc.h>
  33. #include <string.h>
  34. #include "netdissect.h"
  35. /*
  36. * Appends src to string dst of size siz (unlike strncat, siz is the
  37. * full size of dst, not space left). At most siz-1 characters
  38. * will be copied. Always NUL terminates (unless siz == 0).
  39. * Returns strlen(src); if retval >= siz, truncation occurred.
  40. */
  41. size_t
  42. strlcat(char *dst, const char *src, size_t siz)
  43. {
  44. register char *d = dst;
  45. register const char *s = src;
  46. register size_t n = siz;
  47. size_t dlen;
  48. /* Find the end of dst and adjust bytes left but don't go past end */
  49. while (*d != '\0' && n-- != 0)
  50. d++;
  51. dlen = d - dst;
  52. n = siz - dlen;
  53. if (n == 0)
  54. return(dlen + strlen(s));
  55. while (*s != '\0') {
  56. if (n != 1) {
  57. *d++ = *s;
  58. n--;
  59. }
  60. s++;
  61. }
  62. *d = '\0';
  63. return(dlen + (s - src)); /* count does not include NUL */
  64. }