1HASHKIT_FUNCTION(3)          libmemcached-awesome          HASHKIT_FUNCTION(3)
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NAME

6       hashkit_function - libhashkit Documentation
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SYNOPSIS

9       #include <libhashkit-1.0/hashkit.h>
10              Compile and link with -lhashkit
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12       typedef uint32_t (*hashkit_hash_fn)(const char *key, size_t key_length,
13       void *context)
14
15              Parameters
16
17                     • key -- the key to generate a hash of
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19                     • key_length -- the length of the key without any  termi‐
20                       nating zero byte
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22                     • context -- the custom hash function context set through
23                       hashkit_set_custom_function()                        or
24                       hashkit_set_custom_distribution_function()
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26              Returns
27                     the  custom  hash function should return a hash value for
28                     key as an unsigned 32bit integer
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30       typedef enum hashkit_return_t hashkit_return_t
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32       enum hashkit_return_t
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34              enumerator HASHKIT_SUCCESS
35                     Operation succeeded.
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37              enumerator HASHKIT_FAILURE
38                     Operation failed.
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40              enumerator HASHKIT_MEMORY_ALLOCATION_FAILURE
41                     Memory allocation failed.
42
43              enumerator HASHKIT_INVALID_HASH
44                     Invalid hashkit_hash_algorithm_t passed.
45
46              enumerator HASHKIT_INVALID_ARGUMENT
47                     Invalid argument passed.
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49       typedef enum hashkit_hash_algorithm_t hashkit_hash_algorithm_t
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51       enum hashkit_hash_algorithm_t
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53              enumerator HASHKIT_HASH_DEFAULT
54                     Default hash algorithm (one_at_a_time).
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56              enumerator HASHKIT_HASH_MD5
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58              enumerator HASHKIT_HASH_CRC
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60              enumerator HASHKIT_HASH_FNV1_64
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62              enumerator HASHKIT_HASH_FNV1A_64
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64              enumerator HASHKIT_HASH_FNV1_32
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66              enumerator HASHKIT_HASH_FNV1A_32
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68              enumerator HASHKIT_HASH_HSIEH
69                     Only available if libhashkit hash been built  with  HSIEH
70                     support.
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72              enumerator HASHKIT_HASH_MURMUR
73                     Only  available  if libhashkit has been built with MURMUR
74                     support.
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76              enumerator HASHKIT_HASH_MURMUR3
77                     Only available if libhashkit has been built  with  MURMUR
78                     support.
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80              enumerator HASHKIT_HASH_JENKINS
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82              enumerator HASHKIT_HASH_CUSTOM
83                     Use   custom   hashkit_hash_fn   function   set   through
84                     hashkit_set_custom_function()                          or
85                     hashkit_set_custom_distribution_function().
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87       hashkit_return_t         hashkit_set_function(hashkit_st         *hash,
88       hashkit_hash_algorithm_t hash_algorithm)
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90              Parameters
91
92                     • hash -- pointer to an initialized hashkit_st struct
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94                     • hash_algorithm -- valid  hashkit_hash_algorithm_t  con‐
95                       stant
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97              Returns
98                     hashkit_return_t indicating success or failure
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100       hashkit_return_t      hashkit_set_custom_function(hashkit_st     *hash,
101       hashkit_hash_fn function, void *context)
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103              Parameters
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105                     • hash -- pointer to initialized hashkit_st struct
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107                     • function -- hashkit_hash_fn function pointer to use  as
108                       hash function for HASHKIT_HASH_CUSTOM
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110                     • context  --  pointer  to an opaque user managed context
111                       for the custom hash function
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113              Returns
114                     hashkit_return_t indicating success or failure
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116       hashkit_hash_algorithm_t hashkit_get_function(const hashkit_st *hash)
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118              Parameters
119                     hash -- pointer to an initialized hashkit_st struct
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121              Returns
122                     hashkit_hash_algorithm_t  indicating  the  currently  set
123                     hash algorithm to use
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125       hashkit_return_t   hashkit_set_distribution_function(hashkit_st  *hash,
126       hashkit_hash_algorithm_t hash_algorithm)
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128              Parameters
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130                     • hash -- pointer to an initialized hashkit_st struct
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132                     • hash_algorithm --  valid  hashkit_hash_algrothm_t  con‐
133                       stant
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135              Returns
136                     hashkit_return_t indicating success or failure
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138       hashkit_return_t    hashkit_set_custom_distribution_function(hashkit_st
139       *hash, hashkit_hash_fn function, void *context)
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141              Parameters
142
143                     • hash -- pointer to initialized hashkit_st struct
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145                     • function -- hashkit_hash_fn function pointer to use  as
146                       distribution hash function for HASHKIT_HASH_CUSTOM
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148                     • context  --  pointer  to an opaque user managed context
149                       for the custom distribution hash function
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151       hashkit_hash_algorithm_t        hashkit_get_distribution_function(const
152       hashkit_st *hash)
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154              Parameters
155                     hash -- pointer to an initialized hashkit_st struct
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157              Returns
158                     hashkit_hash_algorithm_t  indicating  the  currently  set
159                     distribution hash algorithm to use
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DESCRIPTION

162       These functions are used to set and retrieve the key  and  distribution
163       hash functions.
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RETURN VALUE

166       hashkit_set_function(), hashkit_set_custom_function() and the distribu‐
167       tion equivalents return hashkit_return_t::HASHKIT_SUCCESS on success.
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169       hashkit_get_function() and  hashkit_get_distribution_function()  return
170       hashkit_hash_algorithm_t indicating the hash function used.
171

SEE ALSO

173       libhashkit(3) hashkit_create(3) hashkit_functions(3)
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1781.1                              Sep 20, 2021              HASHKIT_FUNCTION(3)