qbmap.h(3) libqb qbmap.h(3)NAMEqbmap.h-
This provides a map interface to a Patricia trie, hashtable or
skiplist.
SYNOPSIS
#include <stdint.h>
#include <unistd.h>
Defines
#define QB_MAP_NOTIFY_DELETED 1
#define QB_MAP_NOTIFY_REPLACED 2
#define QB_MAP_NOTIFY_INSERTED 4
#define QB_MAP_NOTIFY_RECURSIVE 8
#define QB_MAP_NOTIFY_FREE 16
Typedefs
typedef struct qb_map qb_map_t
This is an opaque data type representing an instance of a map.
typedef struct qb_map_iter qb_map_iter_t
This is an opaque data type representing an iterator instance.
typedef void(* qb_map_notify_fn )(uint32_t event, char *key, void
*old_value, void *value, void *user_data)
typedef int32_t(* qb_map_transverse_fn )(const char *key, void *value,
void *user_data)
Functions
qb_map_t * qb_hashtable_create (size_t max_size)
Create an unsorted map based on a hashtable.
qb_map_t * qb_skiplist_create (void)
Create a sorted map using a skiplist.
qb_map_t * qb_trie_create (void)
Create a sorted map using a Patricia trie or 'Radix tree'.
void qb_trie_dump (qb_map_t *m)
print out the nodes in the trie
int32_t qb_map_notify_add (qb_map_t *m, const char *key,
qb_map_notify_fn fn, int32_t events, void *user_data)
Add a notifier to the map.
int32_t qb_map_notify_del (qb_map_t *m, const char *key,
qb_map_notify_fn fn, int32_t events)
Delete a notifier from the map.
int32_t qb_map_notify_del_2 (qb_map_t *m, const char *key,
qb_map_notify_fn fn, int32_t events, void *user_data)
Delete a notifier from the map (including the userdata).
void qb_map_put (qb_map_t *map, const char *key, const void *value)
Inserts a new key and value into a qb_map_t.
void * qb_map_get (qb_map_t *map, const char *key)
Gets the value corresponding to the given key.
int32_t qb_map_rm (qb_map_t *map, const char *key)
Removes a key/value pair from a map.
size_t qb_map_count_get (qb_map_t *map)
Get the number of items in the map.
void qb_map_foreach (qb_map_t *map, qb_map_transverse_fn func, void
*user_data)
Calls the given function for each of the key/value pairs in the
map.
qb_map_iter_t * qb_map_iter_create (qb_map_t *map)
Create an iterator.
qb_map_iter_t * qb_map_pref_iter_create (qb_map_t *map, const char
*prefix)
Create a prefix iterator.
const char * qb_map_iter_next (qb_map_iter_t *i, void **value)
Get the next item.
void qb_map_iter_free (qb_map_iter_t *i)
free the iterator
void qb_map_destroy (qb_map_t *map)
Destroy the map, removes all the items from the map.
Detailed Description
This provides a map interface to a Patricia trie, hashtable or
skiplist.
Ordering.RS 4 The hashtable is NOT ordered, but ptrie and skiplist are.
Iterating.RS 4 Below is a simple example of how to iterate over a map.
const char *p;
void *data;
qb_map_iter_t *it = qb_map_iter_create(m);
for (p = qb_map_iter_next(it, &data); p; p = qb_map_iter_next(it, &data)) {
printf('%s > %s0, p, (char*) data);
}
qb_map_iter_free(it);
Deletion of items within the iterator is supported. But note do not free theitem memory in the iterator. If you need to free the data items then registerfor a notifier and free the memory there. This is required as the items arereference counted.
qb_map_notify_add(m, NULL, my_map_free_handler,
QB_MAP_NOTIFY_FREE, NULL);
Notifications.RS 4 These allow you to get callbacks when values areinserted/removed or replaced.
Note:
hashtable only supports deletion and replacement notificatins. There is
also a special global callback for freeing deleted and replaced values
(QB_MAP_NOTIFY_FREE).
See also:qb_map_notify_add()qb_map_notify_del_2()Prefix matching.RS 4 The ptrie supports prefixes in the iterator:
it = qb_map_pref_iter_create(m, 'aa');
while ((p = qb_map_iter_next(it, &data)) != NULL) {
printf('%s > %s0, p, (char*)data);
}
qb_map_iter_free(it);
The ptrie also supports prefixes in notifications: (remember to passQB_MAP_NOTIFY_RECURSIVE into the notify_add.
qb_map_notify_add(m, 'root', my_map_notification,
(QB_MAP_NOTIFY_INSERTED|
QB_MAP_NOTIFY_DELETED|
QB_MAP_NOTIFY_REPLACED|
QB_MAP_NOTIFY_RECURSIVE),
NULL);
Define Documentation
#define QB_MAP_NOTIFY_DELETED 1
#define QB_MAP_NOTIFY_FREE 16
#define QB_MAP_NOTIFY_INSERTED 4
#define QB_MAP_NOTIFY_RECURSIVE 8
#define QB_MAP_NOTIFY_REPLACED 2
Typedef Documentation
typedef struct qb_map_iter qb_map_iter_t
This is an opaque data type representing an iterator instance.
typedef void(* qb_map_notify_fn)(uint32_t event, char *key, void
*old_value, void *value, void *user_data)
typedef struct qb_map qb_map_t
This is an opaque data type representing an instance of a map.
typedef int32_t(* qb_map_transverse_fn)(const char *key, void *value, void
*user_data)
Function Documentation
qb_map_t* qb_hashtable_create (size_t max_size)
Create an unsorted map based on a hashtable. Parameters:
max_size maximum size of the hashtable
Returns:
the map instance
size_t qb_map_count_get (qb_map_t * map)
Get the number of items in the map.
void qb_map_destroy (qb_map_t * map)
Destroy the map, removes all the items from the map.
void qb_map_foreach (qb_map_t * map, qb_map_transverse_fn func, void *
user_data)
Calls the given function for each of the key/value pairs in the map.
The function is passed the key and value of each pair, and the given
data parameter. The map is traversed in sorted order.
void* qb_map_get (qb_map_t * map, const char * key)
Gets the value corresponding to the given key. Return values:
NULL (if the key does not exist)
a pointer to the value
qb_map_iter_t* qb_map_iter_create (qb_map_t * map)
Create an iterator.
void qb_map_iter_free (qb_map_iter_t * i)
free the iterator Parameters:
i the iterator
const char* qb_map_iter_next (qb_map_iter_t * i, void ** value)
Get the next item. Parameters:
i the iterator
value (out) the next item's value
Return values:
the next key
NULL - the end of the iteration
int32_t qb_map_notify_add (qb_map_t * m, const char * key, qb_map_notify_fn
fn, int32_t events, void * user_data)
Add a notifier to the map. Parameters:
m the map instance
key the key (or prefix) to attach the notification to.
fn the callback
events the type of events to register for.
user_data a pointer to be passed into the callback
Note:
QB_MAP_NOTIFY_INSERTED is only valid on tries.
you can use key prefixes with trie maps.
Return values:
0 success
-errno failure
int32_t qb_map_notify_del (qb_map_t * m, const char * key, qb_map_notify_fn
fn, int32_t events)
Delete a notifier from the map. Note:
the key,fn and events must match those you added.
Parameters:
m the map instance
key the key (or prefix) to attach the notification to.
fn the callback
events the type of events to register for.
Return values:
0 success
-errno failure
int32_t qb_map_notify_del_2 (qb_map_t * m, const char * key,
qb_map_notify_fn fn, int32_t events, void * user_data)
Delete a notifier from the map (including the userdata). Note:
the key, fn, events and userdata must match those you added.
Parameters:
m the map instance
key the key (or prefix) to attach the notification to.
fn the callback
events the type of events to register for.
user_data a pointer to be passed into the callback
Return values:
0 success
-errno failure
qb_map_iter_t* qb_map_pref_iter_create (qb_map_t * map, const char *
prefix)
Create a prefix iterator. This will iterate over all items with the
given prefix.
Note:
this is only supported by the trie.
void qb_map_put (qb_map_t * map, const char * key, const void * value)
Inserts a new key and value into a qb_map_t. If the key already exists
in the qb_map_t, it gets replaced by the new key.
int32_t qb_map_rm (qb_map_t * map, const char * key)
Removes a key/value pair from a map.
qb_map_t* qb_skiplist_create (void)
Create a sorted map using a skiplist. Returns:
the map instance
qb_map_t* qb_trie_create (void)
Create a sorted map using a Patricia trie or 'Radix tree'.
void qb_trie_dump (qb_map_t * m)
print out the nodes in the trie (for debug purposes)
Author
Generated automatically by Doxygen for libqb from the source code.
Version 0.16.0 21 Nov 2013 qbmap.h(3)
