Mstdlib-1.24.0
Hashtable - uint64/Void Pointer

Typedefs

typedef struct M_hash_u64vp M_hash_u64vp_t
 
typedef struct M_hash_u64vp_enum M_hash_u64vp_enum_t
 

Enumerations

enum  M_hash_u64vp_flags_t {
  M_HASH_U64VP_NONE = 0 ,
  M_HASH_U64VP_KEYS_ORDERED = 1 << 0 ,
  M_HASH_U64VP_KEYS_SORTASC = 1 << 1 ,
  M_HASH_U64VP_KEYS_SORTDESC = 1 << 2 ,
  M_HASH_U64VP_MULTI_VALUE = 1 << 3 ,
  M_HASH_U64VP_MULTI_GETLAST = 1 << 4 ,
  M_HASH_U64VP_STATIC_SEED = 1 << 5
}
 

Functions

M_hash_u64vp_tM_hash_u64vp_create (size_t size, M_uint8 fillpct, M_uint32 flags, void(*destroy_func)(void *)) M_MALLOC_ALIASED
 
void M_hash_u64vp_destroy (M_hash_u64vp_t *h, M_bool destroy_vals) M_FREE(1)
 
M_bool M_hash_u64vp_insert (M_hash_u64vp_t *h, M_uint64 key, void *value)
 
M_bool M_hash_u64vp_remove (M_hash_u64vp_t *h, M_uint64 key, M_bool destroy_vals)
 
M_bool M_hash_u64vp_get (const M_hash_u64vp_t *h, M_uint64 key, void **value)
 
void * M_hash_u64vp_get_direct (const M_hash_u64vp_t *h, M_uint64 key)
 
M_bool M_hash_u64vp_is_multi (const M_hash_u64vp_t *h)
 
M_bool M_hash_u64vp_multi_len (const M_hash_u64vp_t *h, M_uint64 key, size_t *len)
 
M_bool M_hash_u64vp_multi_get (const M_hash_u64vp_t *h, M_uint64 key, size_t idx, void **value)
 
void * M_hash_u64vp_multi_get_direct (const M_hash_u64vp_t *h, M_uint64 key, size_t idx)
 
M_bool M_hash_u64vp_multi_remove (M_hash_u64vp_t *h, M_uint64 key, size_t idx, M_bool destroy_vals)
 
M_uint32 M_hash_u64vp_size (const M_hash_u64vp_t *h)
 
size_t M_hash_u64vp_num_collisions (const M_hash_u64vp_t *h)
 
size_t M_hash_u64vp_num_expansions (const M_hash_u64vp_t *h)
 
size_t M_hash_u64vp_num_keys (const M_hash_u64vp_t *h)
 
size_t M_hash_u64vp_enumerate (const M_hash_u64vp_t *h, M_hash_u64vp_enum_t **hashenum)
 
M_bool M_hash_u64vp_enumerate_next (const M_hash_u64vp_t *h, M_hash_u64vp_enum_t *hashenum, M_uint64 *key, void **value)
 
void M_hash_u64vp_enumerate_free (M_hash_u64vp_enum_t *hashenum)
 
void M_hash_u64vp_merge (M_hash_u64vp_t **dest, M_hash_u64vp_t *src) M_FREE(2)
 

Detailed Description

Hashtable, meant for storing uint64 keys and void pointer values.

References to the data will always be read-only. All keys will be duplicated by the hashtable. Values will not be duplicated.

Typedef Documentation

◆ M_hash_u64vp_t

typedef struct M_hash_u64vp M_hash_u64vp_t

◆ M_hash_u64vp_enum_t

typedef struct M_hash_u64vp_enum M_hash_u64vp_enum_t

Enumeration Type Documentation

◆ M_hash_u64vp_flags_t

Flags for controlling the behavior of the hash

Enumerator
M_HASH_U64VP_NONE 

Case sensitive single value (new values replace).

M_HASH_U64VP_KEYS_ORDERED 

Keys should be ordered. Default is insertion order unless the sorted option is specified.

M_HASH_U64VP_KEYS_SORTASC 

When the keys are ordered sort them using the key_equality function.

M_HASH_U64VP_KEYS_SORTDESC 

When the keys are ordered sort them using the key_equality function.

M_HASH_U64VP_MULTI_VALUE 

Allow keys to contain multiple values. Sorted in insertion order another sorting is specified.

M_HASH_U64VP_MULTI_GETLAST 

When using get and get_direct function get the last value from the list when allowing multiple values. The default is to get the first value.

M_HASH_U64VP_STATIC_SEED 

Use a static seed for hash function initialization. This greatly reduces the security of the hashtable and removes collision attack protections. This should only be used as a performance optimization when creating millions of hashtables with static data specifically for quick look up. DO NOT use this flag with any hashtable that could store user generated data! Be very careful about duplicating a hashtable that was created with this flag. All duplicates will use the static seed.

Function Documentation

◆ M_hash_u64vp_create()

M_hash_u64vp_t * M_hash_u64vp_create ( size_t  size,
M_uint8  fillpct,
M_uint32  flags,
void(*)(void *)  destroy_func 
)

Create a new hashtable.

The hashtable will pre-allocate an array of buckets based on the rounded up size specified. Any hash collisions will result in those collisions being chained together via a linked list. The hashtable will auto-expand by a power of 2 when the fill percentage specified is reached. All key entries are compared in a case-insensitive fashion, and are duplicated internally. Values are duplicated. Case is preserved for both keys and values.

Parameters
[in]sizeSize of the hash table. If not specified as a power of 2, will be rounded up to the nearest power of 2.
[in]fillpctThe maximum fill percentage before the hash table is expanded. If 0 is specified, the hashtable will never expand, otherwise the value must be between 1 and 99 (recommended: 75).
[in]flagsM_hash_strvp_flags_t flags for modifying behavior.
[in]destroy_funcThe function to be called to destroy value when the hashtable itself is destroyed. Can be NULL.
Returns
Allocated hashtable.
See also
M_hash_u64vp_destroy

◆ M_hash_u64vp_destroy()

void M_hash_u64vp_destroy ( M_hash_u64vp_t h,
M_bool  destroy_vals 
)

Destroy the hashtable.

Parameters
[in]hHashtable to destroy
[in]destroy_valsM_TRUE if the values held by the hashtable should be destroyed. This will almost always be M_TRUE. This should only be set to M_FALSE when all values held by the hashtable are being managed externally.

◆ M_hash_u64vp_insert()

M_bool M_hash_u64vp_insert ( M_hash_u64vp_t h,
M_uint64  key,
void *  value 
)

Insert an entry into the hashtable.

Parameters
[in,out]hHashtable being referenced.
[in]keyKey to insert.
[in]valueValue to insert into hashtable. Value will not be duplicated. The hashtable will take ownership of the value. Maybe NULL.
Returns
M_TRUE on success, or M_FALSE on failure.

◆ M_hash_u64vp_remove()

M_bool M_hash_u64vp_remove ( M_hash_u64vp_t h,
M_uint64  key,
M_bool  destroy_vals 
)

Remove an entry from the hashtable.

Parameters
[in,out]hHashtable being referenced.
[in]keyKey to remove from the hashtable.
[in]destroy_valsM_TRUE if the value held by the hashtable should be destroyed. This will almost always be M_TRUE. This should only be set to M_FALSE when the value held by the hashtable is being managed externally.
Returns
M_TRUE on success, or M_FALSE if key does not exist.

◆ M_hash_u64vp_get()

M_bool M_hash_u64vp_get ( const M_hash_u64vp_t h,
M_uint64  key,
void **  value 
)

Retrieve the value for a key from the hashtable.

Parameters
[in]hHashtable being referenced.
[in]keyKey for value.
[out]valuePointer to value stored in the hashtable. Optional, pass NULL if not needed.
Returns
M_TRUE if value retrieved, M_FALSE if key does not exist.

◆ M_hash_u64vp_get_direct()

void * M_hash_u64vp_get_direct ( const M_hash_u64vp_t h,
M_uint64  key 
)

Retrieve the value for a key from the hashtable, and return it directly as the return value.

This cannot be used if you need to differentiate between a key that doesn't exist vs a key with a NULL value.

Parameters
[in]hHashtable being referenced.
[in]keyKey for value to retrieve from the hashtable.
Returns
NULL if key doesn't exist or NULL value on file, otherwise the value.

◆ M_hash_u64vp_is_multi()

M_bool M_hash_u64vp_is_multi ( const M_hash_u64vp_t h)

Wether the hashtable a multi value table.

Parameters
[in]hHashtable being referenced.
Returns
M_TRUE if a multi value hashtable.

◆ M_hash_u64vp_multi_len()

M_bool M_hash_u64vp_multi_len ( const M_hash_u64vp_t h,
M_uint64  key,
size_t *  len 
)

Get the number of values for a given key.

Parameters
[in]hHashtable being referenced.
[in]keyKey for value to retrieve.
[out]lenThe number of values.
Returns
M_TRUE if length is retrieved, M_FALSE if key does not exist.

◆ M_hash_u64vp_multi_get()

M_bool M_hash_u64vp_multi_get ( const M_hash_u64vp_t h,
M_uint64  key,
size_t  idx,
void **  value 
)

Retrieve the value for a key from the given index when supporting muli-values.

Parameters
[in]hHashtable being referenced.
[in]keyKey for value to retrieve.
[in]idxThe index the value resides at.
[out]valuePointer to value stored. Optional, pass NULL if not needed.
Returns
M_TRUE if value retrieved, M_FALSE if key does not exist

◆ M_hash_u64vp_multi_get_direct()

void * M_hash_u64vp_multi_get_direct ( const M_hash_u64vp_t h,
M_uint64  key,
size_t  idx 
)

Retrieve the value for a key from the given index when supporting muli-values.

Parameters
[in]hHashtable being referenced.
[in]keyKey for value to retrieve.
[in]idxThe index the value resides at.
Returns
M_TRUE if value retrieved, M_FALSE if key does not exist.

◆ M_hash_u64vp_multi_remove()

M_bool M_hash_u64vp_multi_remove ( M_hash_u64vp_t h,
M_uint64  key,
size_t  idx,
M_bool  destroy_vals 
)

Remove a value from the hashtable when supporting muli-values.

If all values have been removed then the key will be removed.

Parameters
[in,out]hHashtable being referenced
[in]keyKey for value to retrieve.
[in]idxThe index the value resides at.
[in]destroy_valsM_TRUE if the value held by the hashtable should be destroyed. This will almost always be M_TRUE. This should only be set to M_FALSE when the value held by the hashtable is being managed externally.
Returns
M_TRUE if the value was removed, M_FALSE if key does not exist.

◆ M_hash_u64vp_size()

M_uint32 M_hash_u64vp_size ( const M_hash_u64vp_t h)

Retrieve the current size (number of buckets/slots, not necessarily used).

Parameters
[in]hHashtable being referenced.
Returns
Size of the hashtable

◆ M_hash_u64vp_num_collisions()

size_t M_hash_u64vp_num_collisions ( const M_hash_u64vp_t h)

Retrieve the number of collisions for hashtable entries that has occurred since creation.

Parameters
[in]hHashtable being referenced.
Returns
Number of collisions.

◆ M_hash_u64vp_num_expansions()

size_t M_hash_u64vp_num_expansions ( const M_hash_u64vp_t h)

Retrieve the number of expansions/rehashes since creation.

Parameters
[in]hHashtable being referenced.
Returns
number of expansions/rehashes.

◆ M_hash_u64vp_num_keys()

size_t M_hash_u64vp_num_keys ( const M_hash_u64vp_t h)

Retrieve the number of entries in the hashtable.

This is the number of keys stored.

Parameters
[in]hHashtable being referenced.
Returns
number of entries in the hashtable.

◆ M_hash_u64vp_enumerate()

size_t M_hash_u64vp_enumerate ( const M_hash_u64vp_t h,
M_hash_u64vp_enum_t **  hashenum 
)

Start an enumeration of the keys within a hashtable.

Parameters
[in]hHashtable being referenced.
[out]hashenumOutputs an initialized state variable for starting an enumeration.
Returns
Number of items in the hashtable
See also
M_hash_strvp_enumerate_free

◆ M_hash_u64vp_enumerate_next()

M_bool M_hash_u64vp_enumerate_next ( const M_hash_u64vp_t h,
M_hash_u64vp_enum_t hashenum,
M_uint64 *  key,
void **  value 
)

Retrieve the next item from a hashtable enumeration.

If multi-value, keys will appear multiple times as each value will be retrieved individually.

Parameters
[in]hHashtable being referenced.
[in,out]hashenumState variable for tracking the enumeration process.
[out]keyValue of next enumerated key. Optional, pass NULL if not needed.
[out]valueValue of next enumerated value. Optional, pass NULL if not needed.
Returns
M_TRUE if enumeration succeeded, M_FALSE if no more keys.

◆ M_hash_u64vp_enumerate_free()

void M_hash_u64vp_enumerate_free ( M_hash_u64vp_enum_t hashenum)

Destroy an enumeration state.

Parameters
[in]hashenumEnumeration to destroy.

◆ M_hash_u64vp_merge()

void M_hash_u64vp_merge ( M_hash_u64vp_t **  dest,
M_hash_u64vp_t src 
)

Merge two hashtables together.

The second (src) hashtable will be destroyed automatically upon completion of this function. Any key/value pointers for the hashtable will be directly copied over to the destination hashtable, they will not be duplicated. Any keys which exist in 'dest' that also exist in 'src' will be overwritten by the 'src' value.

If dest and src are multi-value, all values from src will be copied into dest and the values from dest will not be removed. If dest is not multi-value and src is, then only the last value in src will be present in dest. If dest is multi-value and src is not, then the value from src will be added to dest.

Parameters
[in,out]destPointer by reference to the hashtable receiving the key/value pairs. if dest is NULL, the src address will simply be copied to dest.
[in,out]srcPointer to the hashtable giving up its key/value pairs.