2 This file is part of GNUnet.
3 (C) 2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009, 2010 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file include/gnunet_container_lib.h
23 * @brief container classes for GNUnet
25 * @author Christian Grothoff
29 #ifndef GNUNET_CONTAINER_LIB_H
30 #define GNUNET_CONTAINER_LIB_H
32 /* add error and config prototypes */
33 #include "gnunet_crypto_lib.h"
34 #include <extractor.h>
36 #ifndef EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME
37 /* hack for LE < 0.6.3 */
38 #define EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME 180
44 #if 0 /* keep Emacsens' auto-indent happy */
50 /* ******************* bloomfilter ***************** */
53 * @brief bloomfilter representation (opaque)
55 struct GNUNET_CONTAINER_BloomFilter;
58 * Iterator over HashCodes.
61 * @param next set to the next hash code
62 * @return GNUNET_YES if next was updated
63 * GNUNET_NO if there are no more entries
65 typedef int (*GNUNET_HashCodeIterator) (void *cls, GNUNET_HashCode * next);
69 * Load a bloom-filter from a file.
71 * @param filename the name of the file (or the prefix)
72 * @param size the size of the bloom-filter (number of
73 * bytes of storage space to use)
74 * @param k the number of GNUNET_CRYPTO_hash-functions to apply per
75 * element (number of bits set per element in the set)
76 * @return the bloomfilter
78 struct GNUNET_CONTAINER_BloomFilter *GNUNET_CONTAINER_bloomfilter_load (const
88 * Create a bloom filter from raw bits.
90 * @param data the raw bits in memory (maybe NULL,
91 * in which case all bits should be considered
93 * @param size the size of the bloom-filter (number of
94 * bytes of storage space to use); also size of data
95 * -- unless data is NULL. Must be a power of 2.
96 * @param k the number of GNUNET_CRYPTO_hash-functions to apply per
97 * element (number of bits set per element in the set)
98 * @return the bloomfilter
100 struct GNUNET_CONTAINER_BloomFilter *GNUNET_CONTAINER_bloomfilter_init (const
110 * Copy the raw data of this bloomfilter into
111 * the given data array.
113 * @param data where to write the data
114 * @param size the size of the given data array
115 * @return GNUNET_SYSERR if the data array of the wrong size
117 int GNUNET_CONTAINER_bloomfilter_get_raw_data (const struct
118 GNUNET_CONTAINER_BloomFilter
119 *bf, char *data, size_t size);
123 * Test if an element is in the filter.
124 * @param e the element
125 * @param bf the filter
126 * @return GNUNET_YES if the element is in the filter, GNUNET_NO if not
128 int GNUNET_CONTAINER_bloomfilter_test (const struct GNUNET_CONTAINER_BloomFilter
129 *bf, const GNUNET_HashCode * e);
133 * Add an element to the filter
134 * @param bf the filter
135 * @param e the element
137 void GNUNET_CONTAINER_bloomfilter_add (struct GNUNET_CONTAINER_BloomFilter
138 *bf, const GNUNET_HashCode * e);
142 * Remove an element from the filter.
143 * @param bf the filter
144 * @param e the element to remove
146 void GNUNET_CONTAINER_bloomfilter_remove (struct GNUNET_CONTAINER_BloomFilter
147 *bf, const GNUNET_HashCode * e);
151 * Create a copy of a bloomfilter.
153 * @param bf the filter
156 struct GNUNET_CONTAINER_BloomFilter *GNUNET_CONTAINER_bloomfilter_copy (const
158 GNUNET_CONTAINER_BloomFilter
164 * Free the space associcated with a filter
165 * in memory, flush to drive if needed (do not
166 * free the space on the drive)
167 * @param bf the filter
169 void GNUNET_CONTAINER_bloomfilter_free (struct GNUNET_CONTAINER_BloomFilter
174 * Get size of the bloom filter.
176 * @param bf the filter
177 * @return number of bytes used for the data of the bloom filter
191 GNUNET_CONTAINER_bloomfilter_get_size (const struct GNUNET_CONTAINER_BloomFilter
196 * Reset a bloom filter to empty.
197 * @param bf the filter
199 void GNUNET_CONTAINER_bloomfilter_clear (struct GNUNET_CONTAINER_BloomFilter
203 * Or the entries of the given raw data array with the
204 * data of the given bloom filter. Assumes that
205 * the size of the data array and the current filter
208 * @param bf the filter
209 * @param data data to OR-in
210 * @param size size of data
211 * @return GNUNET_OK on success
213 int GNUNET_CONTAINER_bloomfilter_or (struct GNUNET_CONTAINER_BloomFilter *bf,
214 const char *data, size_t size);
217 * Or the entries of the given raw data array with the
218 * data of the given bloom filter. Assumes that
219 * the size of the data array and the current filter
222 * @param bf the filter
223 * @param to_or the bloomfilter to or-in
224 * @param size number of bytes in data
227 GNUNET_CONTAINER_bloomfilter_or2 (struct GNUNET_CONTAINER_BloomFilter *bf,
228 const struct GNUNET_CONTAINER_BloomFilter
229 *to_or, size_t size);
232 * Resize a bloom filter. Note that this operation
233 * is pretty costly. Essentially, the bloom filter
234 * needs to be completely re-build.
236 * @param bf the filter
237 * @param iterator an iterator over all elements stored in the BF
238 * @param iterator_cls closure for iterator
239 * @param size the new size for the filter
240 * @param k the new number of GNUNET_CRYPTO_hash-function to apply per element
242 void GNUNET_CONTAINER_bloomfilter_resize (struct GNUNET_CONTAINER_BloomFilter
244 GNUNET_HashCodeIterator iterator,
246 size_t size, unsigned int k);
248 /* ****************** metadata ******************* */
251 * Meta data to associate with a file, directory or namespace.
253 struct GNUNET_CONTAINER_MetaData;
256 * Create a fresh MetaData token.
258 * @return empty meta-data container
260 struct GNUNET_CONTAINER_MetaData *GNUNET_CONTAINER_meta_data_create (void);
263 * Duplicate a MetaData token.
265 * @param md what to duplicate
266 * @return duplicate meta-data container
268 struct GNUNET_CONTAINER_MetaData *GNUNET_CONTAINER_meta_data_duplicate (const
270 GNUNET_CONTAINER_MetaData
276 * @param md what to free
278 void GNUNET_CONTAINER_meta_data_destroy (struct GNUNET_CONTAINER_MetaData *md);
281 * Test if two MDs are equal. We consider them equal if
282 * the meta types, formats and content match (we do not
283 * include the mime types and plugins names in this
286 * @param md1 first value to check
287 * @param md2 other value to check
288 * @return GNUNET_YES if they are equal
291 GNUNET_CONTAINER_meta_data_test_equal (const struct
292 GNUNET_CONTAINER_MetaData *md1,
294 GNUNET_CONTAINER_MetaData *md2);
300 * @param md metadata to extend
301 * @param plugin_name name of the plugin that produced this value;
302 * special values can be used (i.e. '<zlib>' for zlib being
303 * used in the main libextractor library and yielding
305 * @param type libextractor-type describing the meta data
306 * @param format basic format information about data
307 * @param data_mime_type mime-type of data (not of the original file);
308 * can be NULL (if mime-type is not known)
309 * @param data actual meta-data found
310 * @param data_len number of bytes in data
311 * @return GNUNET_OK on success, GNUNET_SYSERR if this entry already exists
312 * data_mime_type and plugin_name are not considered for "exists" checks
315 GNUNET_CONTAINER_meta_data_insert (struct GNUNET_CONTAINER_MetaData *md,
316 const char *plugin_name,
317 enum EXTRACTOR_MetaType type,
318 enum EXTRACTOR_MetaFormat format,
319 const char *data_mime_type,
320 const char *data, size_t data_len);
324 * Extend metadata. Merges the meta data from the second argument
325 * into the first, discarding duplicate key-value pairs.
327 * @param md metadata to extend
328 * @param in metadata to merge
331 GNUNET_CONTAINER_meta_data_merge (struct GNUNET_CONTAINER_MetaData *md,
332 const struct GNUNET_CONTAINER_MetaData *in);
338 * @param md metadata to manipulate
339 * @param type type of the item to remove
340 * @param data specific value to remove, NULL to remove all
341 * entries of the given type
342 * @param data_len number of bytes in data
343 * @return GNUNET_OK on success, GNUNET_SYSERR if the item does not exist in md
346 GNUNET_CONTAINER_meta_data_delete (struct GNUNET_CONTAINER_MetaData *md,
347 enum EXTRACTOR_MetaType type,
348 const char *data, size_t data_len);
352 * Remove all items in the container.
354 * @param md metadata to manipulate
356 void GNUNET_CONTAINER_meta_data_clear (struct GNUNET_CONTAINER_MetaData *md);
360 * Add the current time as the publication date
363 * @param md metadata to modify
366 GNUNET_CONTAINER_meta_data_add_publication_date (struct
367 GNUNET_CONTAINER_MetaData *md);
371 * Iterate over MD entries.
373 * @param md metadata to inspect
374 * @param iter function to call on each entry
375 * @param iter_cls closure for iterator
376 * @return number of entries
378 int GNUNET_CONTAINER_meta_data_iterate (const struct
379 GNUNET_CONTAINER_MetaData *md,
380 EXTRACTOR_MetaDataProcessor
381 iter, void *iter_cls);
384 * Get the first MD entry of the given type. Caller
385 * is responsible for freeing the return value.
386 * Also, only meta data items that are strings (0-terminated)
387 * are returned by this function.
389 * @param md metadata to inspect
390 * @param type type to look for
391 * @return NULL if no entry was found
393 char *GNUNET_CONTAINER_meta_data_get_by_type (const struct
394 GNUNET_CONTAINER_MetaData *md,
395 enum EXTRACTOR_MetaType type);
399 * Get the first matching MD entry of the given types. Caller is
400 * responsible for freeing the return value. Also, only meta data
401 * items that are strings (0-terminated) are returned by this
404 * @param md metadata to inspect
405 * @param ... -1-terminated list of types
406 * @return NULL if we do not have any such entry,
407 * otherwise client is responsible for freeing the value!
409 char *GNUNET_CONTAINER_meta_data_get_first_by_types (const struct
410 GNUNET_CONTAINER_MetaData
414 * Get a thumbnail from the meta-data (if present). Only matches meta
415 * data with mime type "image" and binary format.
417 * @param md metadata to inspect
418 * @param thumb will be set to the thumbnail data. Must be
419 * freed by the caller!
420 * @return number of bytes in thumbnail, 0 if not available
423 GNUNET_CONTAINER_meta_data_get_thumbnail (const struct
424 GNUNET_CONTAINER_MetaData
425 *md, unsigned char **thumb);
430 * Options for metadata serialization.
432 enum GNUNET_CONTAINER_MetaDataSerializationOptions
435 * Serialize all of the data.
437 GNUNET_CONTAINER_META_DATA_SERIALIZE_FULL = 0,
440 * If not enough space is available, it is acceptable
441 * to only serialize some of the metadata.
443 GNUNET_CONTAINER_META_DATA_SERIALIZE_PART = 1,
446 * Speed is of the essence, do not allow compression.
448 GNUNET_CONTAINER_META_DATA_SERIALIZE_NO_COMPRESS = 2
453 * Serialize meta-data to target.
455 * @param md metadata to serialize
456 * @param target where to write the serialized metadata;
457 * *target can be NULL, in which case memory is allocated
458 * @param max maximum number of bytes available
459 * @param opt is it ok to just write SOME of the
460 * meta-data to match the size constraint,
461 * possibly discarding some data?
462 * @return number of bytes written on success,
463 * -1 on error (typically: not enough
486 GNUNET_CONTAINER_meta_data_serialize (const struct
487 GNUNET_CONTAINER_MetaData *md,
491 GNUNET_CONTAINER_MetaDataSerializationOptions
496 * Get the size of the full meta-data in serialized form.
498 * @param md metadata to inspect
499 * @return number of bytes needed for serialization, -1 on error
521 GNUNET_CONTAINER_meta_data_get_serialized_size (const struct
522 GNUNET_CONTAINER_MetaData *md);
526 * Deserialize meta-data. Initializes md.
528 * @param input serialized meta-data.
529 * @param size number of bytes available
530 * @return MD on success, NULL on error (i.e.
533 struct GNUNET_CONTAINER_MetaData *GNUNET_CONTAINER_meta_data_deserialize (const
540 /* ******************************* HashMap **************************** */
543 * Opaque handle for a HashMap.
545 struct GNUNET_CONTAINER_MultiHashMap;
548 * Options for storing values in the HashMap.
550 enum GNUNET_CONTAINER_MultiHashMapOption
554 * If a value with the given key exists, replace it. Note that the
555 * old value would NOT be freed by replace (the application has to
556 * make sure that this happens if required).
558 GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE,
561 * Allow multiple values with the same key.
563 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE,
566 * There must only be one value per key; storing a value should fail
567 * if a value under the same key already exists.
569 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY,
572 * There must only be one value per key, but don't bother checking
573 * if a value already exists (faster than UNIQUE_ONLY; implemented
574 * just like MULTIPLE but this option documents better what is
575 * intended if UNIQUE is what is desired).
577 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST
582 * Iterator over hash map entries.
585 * @param key current key code
586 * @param value value in the hash map
587 * @return GNUNET_YES if we should continue to
591 typedef int (*GNUNET_CONTAINER_HashMapIterator) (void *cls,
592 const GNUNET_HashCode * key,
597 * Create a multi hash map.
599 * @param len initial size (map will grow as needed)
600 * @return NULL on error
602 struct GNUNET_CONTAINER_MultiHashMap
603 *GNUNET_CONTAINER_multihashmap_create (unsigned int len);
607 * Destroy a hash map. Will not free any values
608 * stored in the hash map!
612 void GNUNET_CONTAINER_multihashmap_destroy (struct
613 GNUNET_CONTAINER_MultiHashMap *map);
617 * Given a key find a value in the map matching the key.
620 * @param key what to look for
621 * @return NULL if no value was found; note that
622 * this is indistinguishable from values that just
623 * happen to be NULL; use "contains" to test for
624 * key-value pairs with value NULL
626 void *GNUNET_CONTAINER_multihashmap_get (const struct
627 GNUNET_CONTAINER_MultiHashMap *map,
628 const GNUNET_HashCode * key);
632 * Remove the given key-value pair from the map. Note that if the
633 * key-value pair is in the map multiple times, only one of the pairs
637 * @param key key of the key-value pair
638 * @param value value of the key-value pair
639 * @return GNUNET_YES on success, GNUNET_NO if the key-value pair
642 int GNUNET_CONTAINER_multihashmap_remove (struct GNUNET_CONTAINER_MultiHashMap
643 *map, const GNUNET_HashCode * key,
647 * Remove all entries for the given key from the map.
648 * Note that the values would not be "freed".
651 * @param key identifies values to be removed
652 * @return number of values removed
654 int GNUNET_CONTAINER_multihashmap_remove_all (struct
655 GNUNET_CONTAINER_MultiHashMap
657 const GNUNET_HashCode * key);
661 * Check if the map contains any value under the given
662 * key (including values that are NULL).
665 * @param key the key to test if a value exists for it
666 * @return GNUNET_YES if such a value exists,
669 int GNUNET_CONTAINER_multihashmap_contains (const struct
670 GNUNET_CONTAINER_MultiHashMap
671 *map, const GNUNET_HashCode * key);
675 * Check if the map contains the given value under the given
679 * @param key the key to test if a value exists for it
680 * @param value value to test for
681 * @return GNUNET_YES if such a value exists,
684 int GNUNET_CONTAINER_multihashmap_contains_value (const struct
685 GNUNET_CONTAINER_MultiHashMap
687 const GNUNET_HashCode * key,
692 * Store a key-value pair in the map.
695 * @param key key to use
696 * @param value value to use
697 * @param opt options for put
698 * @return GNUNET_OK on success,
699 * GNUNET_NO if a value was replaced (with REPLACE)
700 * GNUNET_SYSERR if UNIQUE_ONLY was the option and the
701 * value already exists
703 int GNUNET_CONTAINER_multihashmap_put (struct GNUNET_CONTAINER_MultiHashMap
704 *map, const GNUNET_HashCode * key,
707 GNUNET_CONTAINER_MultiHashMapOption opt);
710 * Get the number of key-value pairs in the map.
713 * @return the number of key value pairs
715 unsigned int GNUNET_CONTAINER_multihashmap_size (const struct
716 GNUNET_CONTAINER_MultiHashMap
721 * Iterate over all entries in the map.
724 * @param it function to call on each entry
725 * @param it_cls extra argument to it
726 * @return the number of key value pairs processed,
727 * GNUNET_SYSERR if it aborted iteration
729 int GNUNET_CONTAINER_multihashmap_iterate (const struct
730 GNUNET_CONTAINER_MultiHashMap *map,
731 GNUNET_CONTAINER_HashMapIterator
736 * Iterate over all entries in the map that match a particular key.
739 * @param key key that the entries must correspond to
740 * @param it function to call on each entry
741 * @param it_cls extra argument to it
742 * @return the number of key value pairs processed,
743 * GNUNET_SYSERR if it aborted iteration
745 int GNUNET_CONTAINER_multihashmap_get_multiple (const struct
746 GNUNET_CONTAINER_MultiHashMap
748 const GNUNET_HashCode * key,
749 GNUNET_CONTAINER_HashMapIterator
753 /* ******************** doubly-linked list *************** */
754 /* To avoid mistakes: head->prev == tail->next == NULL */
757 * Insert an element at the head of a DLL. Assumes that head, tail and
758 * element are structs with prev and next fields.
760 * @param head pointer to the head of the DLL
761 * @param tail pointer to the tail of the DLL
762 * @param element element to insert
764 #define GNUNET_CONTAINER_DLL_insert(head,tail,element) do { \
765 GNUNET_assert ( ( (element)->prev == NULL) && ((head) != (element))); \
766 GNUNET_assert ( ( (element)->next == NULL) && ((tail) != (element))); \
767 (element)->next = (head); \
768 (element)->prev = NULL; \
769 if ((tail) == NULL) \
772 (head)->prev = element; \
773 (head) = (element); } while (0)
777 * Insert an element at the tail of a DLL. Assumes that head, tail and
778 * element are structs with prev and next fields.
780 * @param head pointer to the head of the DLL
781 * @param tail pointer to the tail of the DLL
782 * @param element element to insert
784 #define GNUNET_CONTAINER_DLL_insert_tail(head,tail,element) do { \
785 GNUNET_assert ( ( (element)->prev == NULL) && ((head) != (element))); \
786 GNUNET_assert ( ( (element)->next == NULL) && ((tail) != (element))); \
787 (element)->prev = (tail); \
788 (element)->next = NULL; \
789 if ((head) == NULL) \
792 (tail)->next = element; \
793 (tail) = (element); } while (0)
797 * Insert an element into a DLL after the given other element. Insert
798 * at the head if the other element is NULL.
800 * @param head pointer to the head of the DLL
801 * @param tail pointer to the tail of the DLL
802 * @param other prior element, NULL for insertion at head of DLL
803 * @param element element to insert
805 #define GNUNET_CONTAINER_DLL_insert_after(head,tail,other,element) do { \
806 GNUNET_assert ( ( (element)->prev == NULL) && ((head) != (element))); \
807 GNUNET_assert ( ( (element)->next == NULL) && ((tail) != (element))); \
808 (element)->prev = (other); \
811 (element)->next = (head); \
812 (head) = (element); \
816 (element)->next = (other)->next; \
817 (other)->next = (element); \
819 if (NULL == (element)->next) \
820 (tail) = (element); \
822 (element)->next->prev = (element); } while (0)
826 * Insert an element into a DLL before the given other element. Insert
827 * at the tail if the other element is NULL.
829 * @param head pointer to the head of the DLL
830 * @param tail pointer to the tail of the DLL
831 * @param other prior element, NULL for insertion at head of DLL
832 * @param element element to insert
834 #define GNUNET_CONTAINER_DLL_insert_before(head,tail,other,element) do { \
835 GNUNET_assert ( ( (element)->prev == NULL) && ((head) != (element))); \
836 GNUNET_assert ( ( (element)->next == NULL) && ((tail) != (element))); \
837 (element)->next = (other); \
840 (element)->prev = (tail); \
841 (tail) = (element); \
845 (element)->prev = (other)->prev; \
846 (other)->prev = (element); \
848 if (NULL == (element)->prev) \
849 (head) = (element); \
851 (element)->prev->next = (element); } while (0)
855 * Remove an element from a DLL. Assumes
856 * that head, tail and element are structs
857 * with prev and next fields.
859 * @param head pointer to the head of the DLL
860 * @param tail pointer to the tail of the DLL
861 * @param element element to remove
863 #define GNUNET_CONTAINER_DLL_remove(head,tail,element) do { \
864 GNUNET_assert ( ( (element)->prev != NULL) || ((head) == (element))); \
865 GNUNET_assert ( ( (element)->next != NULL) || ((tail) == (element))); \
866 if ((element)->prev == NULL) \
867 (head) = (element)->next; \
869 (element)->prev->next = (element)->next; \
870 if ((element)->next == NULL) \
871 (tail) = (element)->prev; \
873 (element)->next->prev = (element)->prev; \
874 (element)->next = NULL; \
875 (element)->prev = NULL; } while (0)
879 /* ******************** Heap *************** */
883 * Cost by which elements in a heap can be ordered.
885 typedef uint64_t GNUNET_CONTAINER_HeapCostType;
889 * Heap type, either max or min. Hopefully makes the
890 * implementation more useful.
892 enum GNUNET_CONTAINER_HeapOrder
895 * Heap with the maximum cost at the root.
897 GNUNET_CONTAINER_HEAP_ORDER_MAX,
900 * Heap with the minimum cost at the root.
902 GNUNET_CONTAINER_HEAP_ORDER_MIN
909 struct GNUNET_CONTAINER_Heap;
914 * Handle to a node in a heap.
916 struct GNUNET_CONTAINER_HeapNode;
922 * @param order how should the heap be sorted?
923 * @return handle to the heap
925 struct GNUNET_CONTAINER_Heap *GNUNET_CONTAINER_heap_create (enum
926 GNUNET_CONTAINER_HeapOrder
931 * Destroys the heap. Only call on a heap that
934 * @param heap heap to destroy
936 void GNUNET_CONTAINER_heap_destroy (struct GNUNET_CONTAINER_Heap *heap);
940 * Get element stored at root of heap.
942 * @param heap heap to inspect
943 * @return NULL if heap is empty
945 void *GNUNET_CONTAINER_heap_peek (const struct GNUNET_CONTAINER_Heap *heap);
949 * Get the current size of the heap
951 * @param heap the heap to get the size of
952 * @return number of elements stored
955 GNUNET_CONTAINER_heap_get_size (const struct GNUNET_CONTAINER_Heap *heap);
959 * Get the current cost of the node
961 * @param node the node to get the cost of
962 * @return cost of the node
964 GNUNET_CONTAINER_HeapCostType
965 GNUNET_CONTAINER_heap_node_get_cost (const struct GNUNET_CONTAINER_HeapNode
972 * @param node internal node of the heap
973 * @param element value stored at the node
974 * @param cost cost associated with the node
975 * @return GNUNET_YES if we should continue to iterate,
978 typedef int (*GNUNET_CONTAINER_HeapIterator) (void *cls,
979 struct GNUNET_CONTAINER_HeapNode *
981 GNUNET_CONTAINER_HeapCostType
986 * Iterate over all entries in the heap.
988 * @param heap the heap
989 * @param iterator function to call on each entry
990 * @param iterator_cls closure for iterator
993 GNUNET_CONTAINER_heap_iterate (const struct GNUNET_CONTAINER_Heap *heap,
994 GNUNET_CONTAINER_HeapIterator iterator,
999 * Return a *uniform* random element from the heap. Choose a random
1000 * number between 0 and heap size and then walk directly to it.
1001 * This cost can be between 0 and n, amortized cost of logN.
1003 * @param heap heap to choose random element from
1004 * @param max how many nodes from the heap to choose from
1006 * @return data stored at the chosen random node,
1007 * NULL if the heap is empty.
1010 void *GNUNET_CONTAINER_heap_get_random (struct GNUNET_CONTAINER_Heap *heap,
1015 * Perform a random walk of the tree. The walk is biased
1016 * towards elements closer to the root of the tree (since
1017 * each walk starts at the root and ends at a random leaf).
1018 * The heap internally tracks the current position of the
1021 * @param heap heap to walk
1022 * @return data stored at the next random node in the walk;
1023 * NULL if the tree is empty.
1025 void *GNUNET_CONTAINER_heap_walk_get_next (struct GNUNET_CONTAINER_Heap *heap);
1029 * Inserts a new element into the heap.
1031 * @param heap heap to modify
1032 * @param element element to insert
1033 * @param cost cost for the element
1034 * @return node for the new element
1036 struct GNUNET_CONTAINER_HeapNode *GNUNET_CONTAINER_heap_insert (struct
1037 GNUNET_CONTAINER_Heap
1040 GNUNET_CONTAINER_HeapCostType
1045 * Remove root of the heap.
1047 * @param heap heap to modify
1048 * @return element data stored at the root node
1050 void *GNUNET_CONTAINER_heap_remove_root (struct GNUNET_CONTAINER_Heap *heap);
1054 * Removes a node from the heap.
1056 * @param node node to remove
1057 * @return element data stored at the node, NULL if heap is empty
1059 void *GNUNET_CONTAINER_heap_remove_node (struct GNUNET_CONTAINER_HeapNode
1064 * Updates the cost of any node in the tree
1066 * @param heap heap to modify
1067 * @param node node for which the cost is to be changed
1068 * @param new_cost new cost for the node
1071 GNUNET_CONTAINER_heap_update_cost (struct GNUNET_CONTAINER_Heap *heap,
1072 struct GNUNET_CONTAINER_HeapNode *node,
1073 GNUNET_CONTAINER_HeapCostType new_cost);
1076 /* ******************** Singly linked list *************** */
1079 * Possible ways for how data stored in the linked list
1080 * might be allocated.
1082 enum GNUNET_CONTAINER_SListDisposition
1085 * Single-linked list must copy the buffer.
1087 GNUNET_CONTAINER_SLIST_DISPOSITION_TRANSIENT = 0,
1090 * Data is static, no need to copy or free.
1092 GNUNET_CONTAINER_SLIST_DISPOSITION_STATIC = 2,
1095 * Data is dynamic, do not copy but free when done.
1097 GNUNET_CONTAINER_SLIST_DISPOSITION_DYNAMIC = 4
1103 * Handle to a singly linked list
1105 struct GNUNET_CONTAINER_SList;
1108 * Handle to a singly linked list iterator
1110 struct GNUNET_CONTAINER_SList_Iterator;
1114 * Add a new element to the list
1116 * @param disp memory disposition
1117 * @param buf payload buffer
1118 * @param len length of the buffer
1120 void GNUNET_CONTAINER_slist_add (struct GNUNET_CONTAINER_SList *l,
1121 enum GNUNET_CONTAINER_SListDisposition disp,
1122 const void *buf, size_t len);
1126 * Add a new element to the end of the list
1128 * @param disp memory disposition
1129 * @param buf payload buffer
1130 * @param len length of the buffer
1132 void GNUNET_CONTAINER_slist_add_end (struct GNUNET_CONTAINER_SList *l,
1133 enum GNUNET_CONTAINER_SListDisposition
1134 disp, const void *buf, size_t len);
1138 * Append a singly linked list to another
1139 * @param dst list to append to
1143 GNUNET_CONTAINER_slist_append (struct GNUNET_CONTAINER_SList *dst,
1144 struct GNUNET_CONTAINER_SList *src);
1148 * Create a new singly linked list
1149 * @return the new list
1151 struct GNUNET_CONTAINER_SList *GNUNET_CONTAINER_slist_create (void);
1155 * Destroy a singly linked list
1156 * @param l the list to be destroyed
1158 void GNUNET_CONTAINER_slist_destroy (struct GNUNET_CONTAINER_SList *l);
1162 * Return the beginning of a list
1165 * @return iterator pointing to the beginning, free using "GNUNET_free"
1167 struct GNUNET_CONTAINER_SList_Iterator *GNUNET_CONTAINER_slist_begin (struct
1168 GNUNET_CONTAINER_SList
1177 void GNUNET_CONTAINER_slist_clear (struct GNUNET_CONTAINER_SList *l);
1181 * Check if a list contains a certain element
1183 * @param buf payload buffer to find
1184 * @param len length of the payload (number of bytes in buf)
1186 int GNUNET_CONTAINER_slist_contains (const struct GNUNET_CONTAINER_SList *l,
1187 const void *buf, size_t len);
1191 * Count the elements of a list
1193 * @return number of elements in the list
1195 int GNUNET_CONTAINER_slist_count (const struct GNUNET_CONTAINER_SList *l);
1199 * Remove an element from the list
1200 * @param i iterator that points to the element to be removed
1202 void GNUNET_CONTAINER_slist_erase (struct GNUNET_CONTAINER_SList_Iterator *i);
1206 * Insert an element into a list at a specific position
1207 * @param before where to insert the new element
1208 * @param disp memory disposition
1209 * @param buf payload buffer
1210 * @param len length of the payload
1212 void GNUNET_CONTAINER_slist_insert (struct GNUNET_CONTAINER_SList_Iterator
1214 enum GNUNET_CONTAINER_SListDisposition disp,
1215 const void *buf, size_t len);
1219 * Advance an iterator to the next element
1221 * @return GNUNET_YES on success, GNUNET_NO if the end has been reached
1223 int GNUNET_CONTAINER_slist_next (struct GNUNET_CONTAINER_SList_Iterator *i);
1227 * Check if an iterator points beyond the end of a list
1229 * @return GNUNET_YES if the end has been reached, GNUNET_NO if the iterator
1230 * points to a valid element
1232 int GNUNET_CONTAINER_slist_end (struct GNUNET_CONTAINER_SList_Iterator *i);
1236 * Retrieve the element at a specific position in a list
1239 * @param len set to the payload length
1242 void *GNUNET_CONTAINER_slist_get (const struct GNUNET_CONTAINER_SList_Iterator
1247 * Release an iterator
1250 void GNUNET_CONTAINER_slist_iter_destroy (struct GNUNET_CONTAINER_SList_Iterator
1254 #if 0 /* keep Emacsens' auto-indent happy */
1262 /* ifndef GNUNET_CONTAINER_LIB_H */
1264 /* end of gnunet_container_lib.h */