strsep.c 2.5 KB

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  1. /* $OpenBSD: strsep.c,v 1.6 2005/08/08 08:05:37 espie Exp $ */
  2. /*-
  3. * Copyright (c) 1990, 1993
  4. * The Regents of the University of California. All rights reserved.
  5. *
  6. * Redistribution and use in source and binary forms, with or without
  7. * modification, are permitted provided that the following conditions
  8. * are met:
  9. * 1. Redistributions of source code must retain the above copyright
  10. * notice, this list of conditions and the following disclaimer.
  11. * 2. Redistributions in binary form must reproduce the above copyright
  12. * notice, this list of conditions and the following disclaimer in the
  13. * documentation and/or other materials provided with the distribution.
  14. * 3. Neither the name of the University nor the names of its contributors
  15. * may be used to endorse or promote products derived from this software
  16. * without specific prior written permission.
  17. *
  18. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28. * SUCH DAMAGE.
  29. */
  30. #include <string.h>
  31. #include <stdio.h>
  32. /*
  33. * Get next token from string *stringp, where tokens are possibly-empty
  34. * strings separated by characters from delim.
  35. *
  36. * Writes NULs into the string at *stringp to end tokens.
  37. * delim need not remain constant from call to call.
  38. * On return, *stringp points past the last NUL written (if there might
  39. * be further tokens), or is NULL (if there are definitely no more tokens).
  40. *
  41. * If *stringp is NULL, strsep returns NULL.
  42. */
  43. char *
  44. strsep(char **stringp, const char *delim)
  45. {
  46. char *s;
  47. const char *spanp;
  48. int c, sc;
  49. char *tok;
  50. if ((s = *stringp) == NULL)
  51. return (NULL);
  52. for (tok = s;;) {
  53. c = *s++;
  54. spanp = delim;
  55. do {
  56. if ((sc = *spanp++) == c) {
  57. if (c == 0)
  58. s = NULL;
  59. else
  60. s[-1] = 0;
  61. *stringp = s;
  62. return (tok);
  63. }
  64. } while (sc != 0);
  65. }
  66. /* NOTREACHED */
  67. }