aboutsummaryrefslogtreecommitdiff
path: root/bits/stdlib-bsearch.h
blob: 4dcf90c99a998dd0f22ddcdae1eb110e9721a793 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
/* Perform binary search - inline version.
   Copyright (C) 1991-2023 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

__extern_inline void *
bsearch (const void *__key, const void *__base, size_t __nmemb, size_t __size,
	 __compar_fn_t __compar)
{
  size_t __l, __u, __idx;
  const void *__p;
  int __comparison;

  __l = 0;
  __u = __nmemb;
  while (__l < __u)
    {
      __idx = (__l + __u) / 2;
      __p = (const void *) (((const char *) __base) + (__idx * __size));
      __comparison = (*__compar) (__key, __p);
      if (__comparison < 0)
	__u = __idx;
      else if (__comparison > 0)
	__l = __idx + 1;
      else
	{
#if __GNUC_PREREQ(4, 6)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wcast-qual"
#endif
	  return (void *) __p;
#if __GNUC_PREREQ(4, 6)
# pragma GCC diagnostic pop
#endif
	}
    }

  return NULL;
}