| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. | ||
| 3 | * | ||
| 4 | * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved. | ||
| 5 | * | ||
| 6 | * Redistribution and use in source and binary forms, with or without | ||
| 7 | * modification, are permitted provided that the following conditions are met: | ||
| 8 | * | ||
| 9 | * 1. Redistributions of source code must retain the above copyright | ||
| 10 | * notice, this list of conditions and the following disclaimer. | ||
| 11 | * | ||
| 12 | * 2. Redistributions in binary form must reproduce the above copyright | ||
| 13 | * notice, this list of conditions and the following disclaimer in the | ||
| 14 | * documentation and/or other materials provided with the distribution. | ||
| 15 | * | ||
| 16 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | ||
| 17 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
| 18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
| 19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE | ||
| 20 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | ||
| 21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | ||
| 22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | ||
| 23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | ||
| 24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
| 25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | ||
| 26 | * POSSIBILITY OF SUCH DAMAGE. | ||
| 27 | */ | ||
| 28 | /** | ||
| 29 | * @file hash_key.h | ||
| 30 | * @brief Interface for map implementations. | ||
| 31 | * @author Mike Becker | ||
| 32 | * @author Olaf Wintermann | ||
| 33 | * @copyright 2-Clause BSD License | ||
| 34 | */ | ||
| 35 | |||
| 36 | |||
| 37 | #ifndef UCX_HASH_KEY_H | ||
| 38 | #define UCX_HASH_KEY_H | ||
| 39 | |||
| 40 | #include "common.h" | ||
| 41 | #include "string.h" | ||
| 42 | |||
| 43 | #ifdef __cplusplus | ||
| 44 | extern "C" { | ||
| 45 | #endif | ||
| 46 | |||
| 47 | /** Internal structure for a key within a hash map. */ | ||
| 48 | struct cx_hash_key_s { | ||
| 49 | /** The key data. */ | ||
| 50 | const void *data; | ||
| 51 | /** | ||
| 52 | * The key data length. | ||
| 53 | */ | ||
| 54 | size_t len; | ||
| 55 | /** The hash value of the key data. */ | ||
| 56 | unsigned hash; | ||
| 57 | }; | ||
| 58 | |||
| 59 | /** | ||
| 60 | * Type for a hash key. | ||
| 61 | */ | ||
| 62 | typedef struct cx_hash_key_s CxHashKey; | ||
| 63 | |||
| 64 | /** | ||
| 65 | * Computes a murmur2 32-bit hash. | ||
| 66 | * | ||
| 67 | * You need to initialize @c data and @c len in the key struct. | ||
| 68 | * The hash is then directly written to that struct. | ||
| 69 | * | ||
| 70 | * Usually you should not need this function. | ||
| 71 | * Use cx_hash_key(), instead. | ||
| 72 | * | ||
| 73 | * @note If @c data is @c NULL, the hash is defined as 1574210520. | ||
| 74 | * | ||
| 75 | * @param key the key, the hash shall be computed for | ||
| 76 | * @see cx_hash_key() | ||
| 77 | */ | ||
| 78 | cx_attr_nonnull | ||
| 79 | cx_attr_export | ||
| 80 | void cx_hash_murmur(CxHashKey *key); | ||
| 81 | |||
| 82 | /** | ||
| 83 | * Computes a hash key from a string. | ||
| 84 | * | ||
| 85 | * The string needs to be zero-terminated. | ||
| 86 | * | ||
| 87 | * @param str the string | ||
| 88 | * @return the hash key | ||
| 89 | */ | ||
| 90 | cx_attr_nodiscard | ||
| 91 | cx_attr_cstr_arg(1) | ||
| 92 | cx_attr_export | ||
| 93 | CxHashKey cx_hash_key_str(const char *str); | ||
| 94 | |||
| 95 | /** | ||
| 96 | * Computes a hash key from a byte array. | ||
| 97 | * | ||
| 98 | * @param bytes the array | ||
| 99 | * @param len the length | ||
| 100 | * @return the hash key | ||
| 101 | */ | ||
| 102 | cx_attr_nodiscard | ||
| 103 | cx_attr_access_r(1, 2) | ||
| 104 | cx_attr_export | ||
| 105 | CxHashKey cx_hash_key_bytes( | ||
| 106 | const unsigned char *bytes, | ||
| 107 | size_t len | ||
| 108 | ); | ||
| 109 | |||
| 110 | /** | ||
| 111 | * Computes a hash key for an arbitrary object. | ||
| 112 | * | ||
| 113 | * The computation uses the in-memory representation that might not be | ||
| 114 | * the same on different platforms. Therefore, this hash should not be | ||
| 115 | * used for data exchange with different machines. | ||
| 116 | * | ||
| 117 | * @param obj a pointer to an arbitrary object | ||
| 118 | * @param len the length of object in memory | ||
| 119 | * @return the hash key | ||
| 120 | */ | ||
| 121 | cx_attr_nodiscard | ||
| 122 | cx_attr_access_r(1, 2) | ||
| 123 | cx_attr_export | ||
| 124 | CxHashKey cx_hash_key( | ||
| 125 | const void *obj, | ||
| 126 | size_t len | ||
| 127 | ); | ||
| 128 | |||
| 129 | /** | ||
| 130 | * Computes a hash key from a UCX string. | ||
| 131 | * | ||
| 132 | * @param str the string | ||
| 133 | * @return the hash key | ||
| 134 | */ | ||
| 135 | cx_attr_nodiscard | ||
| 136 | 12 | static inline CxHashKey cx_hash_key_cxstr(cxstring str) { | |
| 137 | 12 | return cx_hash_key(str.ptr, str.length); | |
| 138 | } | ||
| 139 | |||
| 140 | /** | ||
| 141 | * Computes a hash key from a UCX string. | ||
| 142 | * | ||
| 143 | * @param str (@c cxstring or @c cxmutstr) the string | ||
| 144 | * @return (@c CxHashKey) the hash key | ||
| 145 | */ | ||
| 146 | #define cx_hash_key_cxstr(str) cx_hash_key_cxstr(cx_strcast(str)) | ||
| 147 | |||
| 148 | #ifdef __cplusplus | ||
| 149 | } // extern "C" | ||
| 150 | #endif | ||
| 151 | |||
| 152 | #endif // UCX_HASH_KEY_H | ||
| 153 |