src/basic/sort-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include "sort-util.h"
   4 #include "alloc-util.h"
   5
   6 /* hey glibc, APIs with callbacks without a user pointer are so useless */
   7 void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size,
   8                  comparison_userdata_fn_t compar, void *arg) {
   9         size_t l, u, idx;
  10         const void *p;
  11         int comparison;
  12
  13         assert(!size_multiply_overflow(nmemb, size));
  14
  15         l = 0;
  16         u = nmemb;
  17         while (l < u) {
  18                 idx = (l + u) / 2;
  19                 p = (const uint8_t*) base + idx * size;
  20                 comparison = compar(key, p, arg);
  21                 if (comparison < 0)
  22                         u = idx;
  23                 else if (comparison > 0)
  24                         l = idx + 1;
  25                 else
  26                         return (void *)p;
  27         }
  28         return NULL;
  29 }
  30
  31 int cmp_int(const int *a, const int *b) {
  32         return CMP(*a, *b);
  33 }