strcasestr.c 2.4 KB

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  1. /* $OpenBSD: strcasestr.c,v 1.4 2015/08/31 02:53:57 guenther Exp $ */
  2. /* $NetBSD: strcasestr.c,v 1.2 2005/02/09 21:35:47 kleink Exp $ */
  3. /*-
  4. * Copyright (c) 1990, 1993
  5. * The Regents of the University of California. All rights reserved.
  6. *
  7. * This code is derived from software contributed to Berkeley by
  8. * Chris Torek.
  9. *
  10. * Redistribution and use in source and binary forms, with or without
  11. * modification, are permitted provided that the following conditions
  12. * are met:
  13. * 1. Redistributions of source code must retain the above copyright
  14. * notice, this list of conditions and the following disclaimer.
  15. * 2. Redistributions in binary form must reproduce the above copyright
  16. * notice, this list of conditions and the following disclaimer in the
  17. * documentation and/or other materials provided with the distribution.
  18. * 3. Neither the name of the University nor the names of its contributors
  19. * may be used to endorse or promote products derived from this software
  20. * without specific prior written permission.
  21. *
  22. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32. * SUCH DAMAGE.
  33. */
  34. /* OPENBSD ORIGINAL: lib/libc/string/strcasestr.c */
  35. #include "includes.h"
  36. #ifndef HAVE_STRCASESTR
  37. #include <ctype.h>
  38. #include <string.h>
  39. /*
  40. * Find the first occurrence of find in s, ignore case.
  41. */
  42. char *
  43. strcasestr(const char *s, const char *find)
  44. {
  45. char c, sc;
  46. size_t len;
  47. if ((c = *find++) != 0) {
  48. c = (char)tolower((unsigned char)c);
  49. len = strlen(find);
  50. do {
  51. do {
  52. if ((sc = *s++) == 0)
  53. return (NULL);
  54. } while ((char)tolower((unsigned char)sc) != c);
  55. } while (strncasecmp(s, find, len) != 0);
  56. s--;
  57. }
  58. return ((char *)s);
  59. }
  60. DEF_WEAK(strcasestr);
  61. #endif