strrchr.c 1.3 KB

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  1. /* Copyright (C) 1991-2019 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. The GNU C Library is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU Lesser General Public
  5. License as published by the Free Software Foundation; either
  6. version 2.1 of the License, or (at your option) any later version.
  7. The GNU C Library is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  10. Lesser General Public License for more details.
  11. You should have received a copy of the GNU Lesser General Public
  12. License along with the GNU C Library; if not, see
  13. <http://www.gnu.org/licenses/>. */
  14. #include <string.h>
  15. #undef strrchr
  16. #ifndef STRRCHR
  17. # define STRRCHR strrchr
  18. #endif
  19. /* Find the last occurrence of C in S. */
  20. char *
  21. STRRCHR (const char *s, int c)
  22. {
  23. const char *found, *p;
  24. c = (unsigned char) c;
  25. /* Since strchr is fast, we use it rather than the obvious loop. */
  26. if (c == '\0')
  27. return strchr (s, '\0');
  28. found = NULL;
  29. while ((p = strchr (s, c)) != NULL)
  30. {
  31. found = p;
  32. s = p + 1;
  33. }
  34. return (char *) found;
  35. }
  36. #ifdef weak_alias
  37. #undef rindex
  38. weak_alias (strrchr, rindex)
  39. #endif
  40. libc_hidden_builtin_def (strrchr)