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 13 const 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