Set Hash Function¶
SYNOPSIS¶
- #include <libhashkit-1.0/hashkit.h>
Compile and link with -lhashkit
-
typedef uint32_t (*hashkit_hash_fn)(const char *key, size_t key_length, void *context)¶
- Parameters
key -- the key to generate a hash of
key_length -- the length of the
key
without any terminating zero bytecontext -- the custom hash function context set through
hashkit_set_custom_function()
orhashkit_set_custom_distribution_function()
- Returns
the custom hash function should return a hash value for
key
as an unsigned 32bit integer
-
typedef enum hashkit_return_t hashkit_return_t¶
-
enum hashkit_return_t¶
-
enumerator HASHKIT_SUCCESS¶
Operation succeeded.
-
enumerator HASHKIT_FAILURE¶
Operation failed.
-
enumerator HASHKIT_MEMORY_ALLOCATION_FAILURE¶
Memory allocation failed.
-
enumerator HASHKIT_INVALID_HASH¶
Invalid
hashkit_hash_algorithm_t
passed.
-
enumerator HASHKIT_INVALID_ARGUMENT¶
Invalid argument passed.
-
enumerator HASHKIT_SUCCESS¶
-
typedef enum hashkit_hash_algorithm_t hashkit_hash_algorithm_t¶
-
enum hashkit_hash_algorithm_t¶
-
enumerator HASHKIT_HASH_DEFAULT¶
Default hash algorithm (one_at_a_time).
-
enumerator HASHKIT_HASH_MD5¶
-
enumerator HASHKIT_HASH_CRC¶
-
enumerator HASHKIT_HASH_FNV1_64¶
-
enumerator HASHKIT_HASH_FNV1A_64¶
-
enumerator HASHKIT_HASH_FNV1_32¶
-
enumerator HASHKIT_HASH_FNV1A_32¶
-
enumerator HASHKIT_HASH_HSIEH¶
Only available if
libhashkit
hash been built with HSIEH support.
-
enumerator HASHKIT_HASH_MURMUR¶
Only available if
libhashkit
has been built with MURMUR support.
-
enumerator HASHKIT_HASH_MURMUR3¶
Only available if
libhashkit
has been built with MURMUR support.
-
enumerator HASHKIT_HASH_JENKINS¶
-
enumerator HASHKIT_HASH_CUSTOM¶
Use custom
hashkit_hash_fn
function set throughhashkit_set_custom_function()
orhashkit_set_custom_distribution_function()
.
-
enumerator HASHKIT_HASH_DEFAULT¶
-
hashkit_return_t hashkit_set_function(hashkit_st *hash, hashkit_hash_algorithm_t hash_algorithm)¶
- Parameters
hash -- pointer to an initialized
hashkit_st
structhash_algorithm -- valid
hashkit_hash_algorithm_t
constant
- Returns
hashkit_return_t
indicating success or failure
-
hashkit_return_t hashkit_set_custom_function(hashkit_st *hash, hashkit_hash_fn function, void *context)¶
- Parameters
hash -- pointer to initialized
hashkit_st
structfunction --
hashkit_hash_fn
function pointer to use as hash function forHASHKIT_HASH_CUSTOM
context -- pointer to an opaque user managed context for the custom hash function
- Returns
hashkit_return_t
indicating success or failure
-
hashkit_hash_algorithm_t hashkit_get_function(const hashkit_st *hash)¶
- Parameters
hash -- pointer to an initialized
hashkit_st
struct- Returns
hashkit_hash_algorithm_t
indicating the currently set hash algorithm to use
-
hashkit_return_t hashkit_set_distribution_function(hashkit_st *hash, hashkit_hash_algorithm_t hash_algorithm)¶
- Parameters
hash -- pointer to an initialized
hashkit_st
structhash_algorithm -- valid
hashkit_hash_algrothm_t
constant
- Returns
hashkit_return_t
indicating success or failure
-
hashkit_return_t hashkit_set_custom_distribution_function(hashkit_st *hash, hashkit_hash_fn function, void *context)¶
- Parameters
hash -- pointer to initialized
hashkit_st
structfunction --
hashkit_hash_fn
function pointer to use as distribution hash function forHASHKIT_HASH_CUSTOM
context -- pointer to an opaque user managed context for the custom distribution hash function
-
hashkit_hash_algorithm_t hashkit_get_distribution_function(const hashkit_st *hash)¶
- Parameters
hash -- pointer to an initialized
hashkit_st
struct- Returns
hashkit_hash_algorithm_t
indicating the currently set distribution hash algorithm to use
DESCRIPTION¶
These functions are used to set and retrieve the key and distribution hash functions.
RETURN VALUE¶
hashkit_set_function()
, hashkit_set_custom_function()
and the distribution
equivalents return hashkit_return_t::HASHKIT_SUCCESS
on success.
hashkit_get_function()
and hashkit_get_distribution_function()
return
hashkit_hash_algorithm_t
indicating the hash function used.