lsearch.c 1.5 KB

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  1. /* Linear search functions.
  2. Copyright (C) 1996-2026 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. #include <search.h>
  16. #include <string.h>
  17. void *
  18. lsearch (const void *key, void *base, size_t *nmemb, size_t size,
  19. __compar_fn_t compar)
  20. {
  21. void *result;
  22. /* Try to find it. */
  23. result = lfind (key, base, nmemb, size, compar);
  24. if (result == NULL)
  25. {
  26. /* Not available. Insert at the end. */
  27. result = memcpy (base + (*nmemb) * size, key, size);
  28. ++(*nmemb);
  29. }
  30. return result;
  31. }
  32. void *
  33. lfind (const void *key, const void *base, size_t *nmemb, size_t size,
  34. __compar_fn_t compar)
  35. {
  36. const void *result = base;
  37. size_t cnt = 0;
  38. while (cnt < *nmemb && (*compar) (key, result) != 0)
  39. {
  40. result += size;
  41. ++cnt;
  42. }
  43. return cnt < *nmemb ? (void *) result : NULL;
  44. }
  45. libc_hidden_def (lfind)