stdlib-bsearch.h 1.5 KB

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  1. /* Perform binary search - inline version.
  2. Copyright (C) 1991-2026 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <https://www.gnu.org/licenses/>. */
  15. __extern_inline void *
  16. bsearch (const void *__key, const void *__base, size_t __nmemb, size_t __size,
  17. __compar_fn_t __compar)
  18. {
  19. const void *__p;
  20. int __comparison;
  21. while (__nmemb)
  22. {
  23. __p = (const void *) (((const char *) __base) + ((__nmemb >> 1) * __size));
  24. __comparison = (*__compar) (__key, __p);
  25. if (__comparison == 0)
  26. {
  27. #if __GNUC_PREREQ(4, 6)
  28. # pragma GCC diagnostic push
  29. # pragma GCC diagnostic ignored "-Wcast-qual"
  30. #endif
  31. return (void *) __p;
  32. #if __GNUC_PREREQ(4, 6)
  33. # pragma GCC diagnostic pop
  34. #endif
  35. }
  36. if (__comparison > 0)
  37. {
  38. __base = ((const char *) __p) + __size;
  39. --__nmemb;
  40. }
  41. __nmemb >>= 1;
  42. }
  43. return NULL;
  44. }