quakeforge/libs/util/test/test-bsearch.c
Bill Currie bcc5686606 [util] Add fuzzy and reentrant bsearch
Fuzzy bsearch is useful for finding an entry in a prefix sum array
(value is >= ele[0], < ele[1]), and the reentrant version is good when
data needs to be passed to the compare function. Adapted from the code
used in pr_resolve.
2021-06-01 18:53:53 +09:00

116 lines
2.6 KiB
C

/*
test-bsearch.c
Fuzzy and reentrant bsearch
Copyright (C) 2021 Bill Currie <bill@taniwha.org>
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include "QF/fbsearch.h"
#include "bsearch.h"
// will be prefix-summed
int data[] = {
2, 1, 3, 1, 2, 2, 5, 4,
2, 1, 3, 1, 2, 2, 5, 4,
};
#define nele ((int) (sizeof (data) / sizeof (data[0])))
static int
compare (const void *a, const void *b)
{
return *(const int *)a - *(const int *)b;
}
static int
compared (const void *a, const void *b, void *d)
{
return *(const int *)a - *(const int *)b;
}
static int
fuzzy_check (const int *p, int val, const char *func)
{
if (val < data[0] && p) {
printf ("%s found %d, but should not\n", func, val);
return 0;
}
if (p) {
int ok = p < data + nele - 1;
if (p >= data + nele) {
printf ("%s went out of bounts: %zd\n", func, p - data);
return 0;
}
if (val < *p || (ok && val >= p[1])) {
printf ("%s found %d:%d for %d\n", func, *p, ok ? p[1] : -1, val);
return 0;
}
}
if (!p && val >= data[0]) {
printf ("%s did not find %d, but should have\n", func, val);
return 0;
}
return 1;
}
int
main(int argc, const char **argv)
{
int ret = 0;
int *p;
for (int i = 1; i < nele; i++) {
data[i] += data[i - 1];
}
for (int i = 0; i < nele; i++) {
printf ("%2d %d\n", i, data[i]);
}
for (int i = 0; i < data[nele - 1] + 2; i++) {
p = fbsearch (&i, data, nele, sizeof (int), compare);
if (!fuzzy_check (p, i, "fbsearch")) {
ret |= 1;
}
p = fbsearch_r (&i, data, nele, sizeof (int), compared, 0);
if (!fuzzy_check (p, i, "fbsearch_r")) {
ret |= 1;
}
if (p && i == *p) {
p = _bsearch (&i, data, nele, sizeof (int), compared, 0);
if (!p || *p != i) {
printf ("_bsearch did not find %d, but should have\n", i);
ret |= 1;
}
} else {
p = _bsearch (&i, data, nele, sizeof (int), compared, 0);
if (p) {
printf ("_bsearch found %d, but should not have\n", i);
ret |= 1;
}
}
}
return ret;
}