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