1 /*
2 * Copyright (c) 2019 Balaji Kulkarni
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <stdlib.h>
8 #include <stdio.h>
9
10 /**
11 * @brief Generic implementation of Binary Search
12 *
13 * @param key pointer to first element to search
14 * @param array pointer to item being searched for
15 * @param count number of elements
16 * @param size size of each element
17 * @param cmp pointer to comparison function
18 *
19 * @return pointer to key if present in the array, or NULL otherwise
20 */
21
bsearch(const void * key,const void * array,size_t count,size_t size,int (* cmp)(const void * key,const void * element))22 void *bsearch(const void *key, const void *array, size_t count, size_t size,
23 int (*cmp)(const void *key, const void *element))
24 {
25 size_t low = 0;
26 size_t high = count;
27 size_t index;
28 int result;
29 const char *pivot;
30
31 while (low < high) {
32 index = low + (high - low) / 2;
33 pivot = (const char *)array + index * size;
34 result = cmp(key, pivot);
35
36 if (result == 0) {
37 return (void *)pivot;
38 } else if (result > 0) {
39 low = index + 1;
40 } else {
41 high = index;
42
43 }
44 }
45 return NULL;
46 }
47
