glibc/misc/lsearch.c

59 lines
1.6 KiB
C

/* Linear search functions.
Copyright (C) 1996-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
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/>. */
#include <search.h>
#include <string.h>
void *
lsearch (const void *key, void *base, size_t *nmemb, size_t size,
__compar_fn_t compar)
{
void *result;
/* Try to find it. */
result = lfind (key, base, nmemb, size, compar);
if (result == NULL)
{
/* Not available. Insert at the end. */
result = memcpy (base + (*nmemb) * size, key, size);
++(*nmemb);
}
return result;
}
void *
lfind (const void *key, const void *base, size_t *nmemb, size_t size,
__compar_fn_t compar)
{
const void *result = base;
size_t cnt = 0;
while (cnt < *nmemb && (*compar) (key, result) != 0)
{
result += size;
++cnt;
}
return cnt < *nmemb ? (void *) result : NULL;
}
libc_hidden_def (lfind)