|
WS_DLL_PUBLIC wmem_multimap_t * | wmem_multimap_new (wmem_allocator_t *allocator, GHashFunc hash_func, GEqualFunc eql_func) G_GNUC_MALLOC |
|
WS_DLL_PUBLIC wmem_multimap_t * | wmem_multimap_new_autoreset (wmem_allocator_t *metadata_scope, wmem_allocator_t *data_scope, GHashFunc hash_func, GEqualFunc eql_func) G_GNUC_MALLOC |
|
WS_DLL_PUBLIC wmem_list_t * | wmem_multimap_get_keys (wmem_allocator_t *list_allocator, wmem_multimap_t *map) |
|
WS_DLL_PUBLIC unsigned | wmem_multimap_size (wmem_multimap_t *map) |
|
WS_DLL_PUBLIC unsigned | wmem_multimap_count (wmem_multimap_t *map, const void *key) |
|
WS_DLL_PUBLIC bool | wmem_multimap_insert32 (wmem_multimap_t *map, const void *key, uint32_t frame_num, void *value) |
|
WS_DLL_PUBLIC void * | wmem_multimap_lookup32 (wmem_multimap_t *map, const void *key, const uint32_t frame_num) |
|
WS_DLL_PUBLIC void * | wmem_multimap_lookup32_le (wmem_multimap_t *map, const void *key, const uint32_t frame_num) |
|
WS_DLL_PUBLIC void * | wmem_multimap_remove32 (wmem_multimap_t *map, const void *key, const uint32_t frame_num) |
|
A hash multimap implementation on top of wmem_map and wmem_tree, storing multiple values at each hash key in a tree indexed by a 32 bit integer.
The primary use case is a protocol with an ID used as the hash lookup key that can be reused in a capture, and the frame number used as the tree key. We often want to find the most recent frame that had a certain ID, e.g. for request/response matching, and wmem_multimap_lookup32_le() serves that purpose.
Since the tree implementation is a self-balancing red-black tree, lookup time is still O(log(n)) even though elements with equivalent hash keys are usually added in increasing order of frame number.
NOTE: The multimap does not yet support inserting items without specifying the tree key, because the total capacity of individual trees (including deleted nodes) is not tracked.
◆ wmem_multimap_count()
WS_DLL_PUBLIC unsigned wmem_multimap_count |
( |
wmem_multimap_t * |
map, |
|
|
const void * |
key |
|
) |
| |
Returns the number of values in the multimap with a certain hash key. (Note: This is the number of current elements, so this can only be used to safely generate unique tree keys prior to insertion if no values have been removed, due to how the tree implementation works.)
- Parameters
-
map | The multimap to search in. |
key | The primary key to lookup in the map. |
- Returns
- The number of values in the tree stored at map key, or zero if no tree exists at that key.
◆ wmem_multimap_get_keys()
Retrieves a list of the keys inside the multimap
- Parameters
-
list_allocator | The allocator scope for the returned list. |
map | The multimap to extract keys from |
- Returns
- list of keys in the multimap
◆ wmem_multimap_insert32()
WS_DLL_PUBLIC bool wmem_multimap_insert32 |
( |
wmem_multimap_t * |
map, |
|
|
const void * |
key, |
|
|
uint32_t |
frame_num, |
|
|
void * |
value |
|
) |
| |
Insert a value in the multimap.
- Parameters
-
map | The multimap to insert into. |
key | The key to insert by in the map. |
frame_num | The key to insert by in the tree. |
value | The value to insert. |
- Returns
- true if there was already a tree mapped at key, in which case the caller may safely free key. (This is not necessary if key is allocated with a wmem pool.)
Note: as with wmem_tree, if there is already a node with the same pair of keys, then the existing value will simply be overwritten. This is not a problem if the value is wmem allocated, but if it is manually managed, then you must ensure that the pair is unique or do a lookup before inserting.
◆ wmem_multimap_lookup32()
WS_DLL_PUBLIC void * wmem_multimap_lookup32 |
( |
wmem_multimap_t * |
map, |
|
|
const void * |
key, |
|
|
const uint32_t |
frame_num |
|
) |
| |
Lookup a value in the multimap combination with an exact match.
- Parameters
-
map | The multimap to search in. |
key | The primary key to lookup in the map. |
frame_num | The secondary key to lookup in the tree. |
- Returns
- The value stored at the keys if any, or NULL.
◆ wmem_multimap_lookup32_le()
WS_DLL_PUBLIC void * wmem_multimap_lookup32_le |
( |
wmem_multimap_t * |
map, |
|
|
const void * |
key, |
|
|
const uint32_t |
frame_num |
|
) |
| |
Lookup a value in the multimap with an exact match for the map key and the largest value less than or equal to the tree key. This is useful for request/response matching where IDs can be reused.
- Parameters
-
map | The multimap to search in. |
key | The primary key to lookup in the map. |
frame_num | The secondary key to lookup in the tree. |
- Returns
- The value stored at the primary key in the map and with the largest key in the tree that is less than or equal to the second key if any, or NULL.
◆ wmem_multimap_new()
Creates a multimap with the given allocator scope. When the scope is emptied, the map is fully destroyed. Items stored in it will not be freed unless they were allocated from the same scope.
- Parameters
-
allocator | The allocator scope with which to create the map. |
hash_func | The hash function used to place inserted keys. |
eql_func | The equality function used to compare inserted keys. |
- Returns
- The newly-allocated map.
◆ wmem_multimap_new_autoreset()
Creates a multimap with two allocator scopes. The base structure lives in the metadata scope, and the map data lives in the data scope. Every time free_all occurs in the data scope the map is transparently emptied without affecting the location of the base / metadata structure.
WARNING: None of the map (even the part in the metadata scope) can be used after the data scope has been destroyed.
The primary use for this function is to create maps that reset for each new capture file that is loaded. This can be done by specifying wmem_epan_scope() as the metadata scope and wmem_file_scope() as the data scope.
◆ wmem_multimap_remove32()
WS_DLL_PUBLIC void * wmem_multimap_remove32 |
( |
wmem_multimap_t * |
map, |
|
|
const void * |
key, |
|
|
const uint32_t |
frame_num |
|
) |
| |
Remove a value from the multimap. If no value is stored at that key pair, nothing happens. As with wmem_tree, this is not really a remove, but the value is set to NULL so that wmem_multimap_lookup32 not will find it.
- Parameters
-
map | The multimap to remove from. |
key | The map key of the value to remove. |
frame_num | The tree key of the value to remove. |
- Returns
- The (removed) value stored at the key if any, or NULL.
◆ wmem_multimap_size()
Return the total number of elements in the multimap.
- Parameters
-
- Returns
- the number of elements