git.m6w6.name Git - awesomized/libmemcached/blob - libhashkit/hashkit.h

   1 /* HashKit
   2  * Copyright (C) 2009 Brian Aker
   3  * All rights reserved.
   4  *
   5  * Use and distribution licensed under the BSD license.  See
   6  * the COPYING file in the parent directory for full text.
   7  */
   8
   9 /**
  10  * @file
  11  * @brief HashKit Header
  12  */
  13
  14 #ifndef HASHKIT_H
  15 #define HASHKIT_H
  16
  17 #if !defined(__cplusplus)
  18 # include <stdbool.h>
  19 #endif
  20 #include <inttypes.h>
  21 #include <sys/types.h>
  22 #include <libhashkit/visibility.h>
  23 #include <libhashkit/types.h>
  24 #include <libhashkit/algorithm.h>
  25 #include <libhashkit/behavior.h>
  26 #include <libhashkit/strerror.h>
  27
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 /**
  33  * @addtogroup hashkit_constants Constants
  34  * @ingroup hashkit
  35  * @{
  36  */
  37
  38 /* Defines. */
  39 #define HASHKIT_MAX_KEY 251
  40 #define HASHKIT_POINTS_PER_NODE 100
  41 #define HASHKIT_POINTS_PER_NODE_WEIGHTED 160
  42 #define HASHKIT_CONTINUUM_ADDITION 10
  43 #define HASHKIT_CONTINUUM_KEY_SIZE 86
  44
  45 /** @} */
  46
  47 /**
  48  * @ingroup hashkit
  49  */
  50 struct hashkit_st
  51 {
  52   hashkit_options_st options;
  53   hashkit_distribution_t distribution;
  54   uint32_t continuum_count;
  55   uint32_t continuum_points_count;
  56   size_t list_size;
  57   size_t context_size;
  58
  59   /**
  60     @note There are two places we use hashing, one is for when we have a key
  61     and we want to find out what server it should be placed on. The second is
  62     for when we are placing a value into the continuum.
  63   */
  64   hashkit_hash_algorithm_t for_key;
  65   hashkit_hash_algorithm_t for_distribution;
  66
  67   hashkit_continuum_point_st *continuum;
  68   hashkit_fn *hash_fn;
  69   hashkit_active_fn *active_fn;
  70   hashkit_fn *continuum_hash_fn;
  71   hashkit_key_fn *continuum_key_fn;
  72   hashkit_sort_fn *sort_fn;
  73   hashkit_weight_fn *weight_fn;
  74   void *list;
  75 };
  76
  77 /**
  78  * @ingroup hashkit
  79  */
  80 struct hashkit_continuum_point_st
  81 {
  82   uint32_t index;
  83   uint32_t value;
  84 };
  85
  86 /**
  87  * @addtogroup hashkit Pandora Hash Declarations
  88  * @{
  89  */
  90
  91 HASHKIT_API
  92 hashkit_st *hashkit_create(hashkit_st *hash);
  93
  94 HASHKIT_API
  95 hashkit_st *hashkit_clone(hashkit_st *destination, const hashkit_st *ptr);
  96
  97 HASHKIT_API
  98 void hashkit_free(hashkit_st *hash);
  99
 100 HASHKIT_API
 101 uint32_t hashkit_generate_value(const char *key, size_t key_length, hashkit_hash_algorithm_t hash_algorithm);
 102
 103 #define hashkit_is_allocated(__object) ((__object)->options.is_allocated)
 104 #define hashkit_is_initialized(__object) ((__object)->options.is_initialized)
 105
 106 /** @} */
 107
 108 #ifdef __cplusplus
 109 }
 110 #endif
 111
 112 #endif /* HASHKIT_H */