mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-23 05:20:06 +00:00
49 lines
1.4 KiB
C
49 lines
1.4 KiB
C
/* Copyright (C) 1991,92,97,2000,02 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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <stdlib.h>
|
|
|
|
|
|
/* Perform a binary search for KEY in BASE which has NMEMB elements
|
|
of SIZE bytes each. The comparisons are done by (*COMPAR)(). */
|
|
void *
|
|
bsearch (const void *key, const void *base, size_t nmemb, size_t size,
|
|
int (*compar) (const void *, const void *))
|
|
{
|
|
size_t l, u, idx;
|
|
const void *p;
|
|
int comparison;
|
|
|
|
l = 0;
|
|
u = nmemb;
|
|
while (l < u)
|
|
{
|
|
idx = (l + u) / 2;
|
|
p = (void *) (((const char *) base) + (idx * size));
|
|
comparison = (*compar) (key, p);
|
|
if (comparison < 0)
|
|
u = idx;
|
|
else if (comparison > 0)
|
|
l = idx + 1;
|
|
else
|
|
return (void *) p;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
libc_hidden_def (bsearch)
|