1/*
2 * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stddef.h>
11#include "internal/cryptlib.h"
12
13const void *ossl_bsearch(const void *key, const void *base, int num,
14                         int size, int (*cmp) (const void *, const void *),
15                         int flags)
16{
17    const char *base_ = base;
18    int l, h, i = 0, c = 0;
19    const char *p = NULL;
20
21    if (num == 0)
22        return NULL;
23    l = 0;
24    h = num;
25    while (l < h) {
26        i = (l + h) / 2;
27        p = &(base_[i * size]);
28        c = (*cmp) (key, p);
29        if (c < 0)
30            h = i;
31        else if (c > 0)
32            l = i + 1;
33        else
34            break;
35    }
36    if (c != 0 && !(flags & OSSL_BSEARCH_VALUE_ON_NOMATCH))
37        p = NULL;
38    else if (c == 0 && (flags & OSSL_BSEARCH_FIRST_VALUE_ON_MATCH)) {
39        while (i > 0 && (*cmp) (key, &(base_[(i - 1) * size])) == 0)
40            i--;
41        p = &(base_[i * size]);
42    }
43    return p;
44}
45