/*
This file is part of GNUnet.
- Copyright (C) 2001-2015 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2001-2015 GNUnet e.V.
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
*/
/**
- * @file include/gnunet_container_lib.h
- * @brief container classes for GNUnet
* @author Christian Grothoff
* @author Nils Durner
- * @defgroup hashmap multi hash-map
- * @defgroup heap min- or max-heap with arbitrary element removal
- * @defgroup bloomfilter Bloom filter (probabilistic set tests)
- * @defgroup dll Doubly-linked list
- * @defgroup metadata Meta data (GNU libextractor key-value pairs)
+ *
+ * @file
+ * Container classes for GNUnet
+ *
+ * @defgroup hashmap Container library: MultiHashMap
+ * Hash map with multiple values per key.
+ *
+ * @see [Documentation](https://gnunet.org/util_multihashmap)
+ *
+ * @defgroup heap Container library: Heap
+ * Min- or max-heap with arbitrary element removal
+ *
+ * @defgroup bloomfilter Container library: Bloom filter
+ * Probabilistic set tests
+ *
+ * @defgroup dll Container library: Doubly-linked list
+ *
+ * @see [Documentation](https://gnunet.org/mdll-api)
+ *
+ * @defgroup metadata Container library: Metadata
+ * GNU libextractor key-value pairs
*/
#ifndef GNUNET_CONTAINER_LIB_H
/* add error and config prototypes */
#include "gnunet_crypto_lib.h"
-#if HAVE_EXTRACTOR_H && HAVE_LIBEXTRACTOR
-#include <extractor.h>
+/**
+ * Try to compress the given block of data using libz. Only returns
+ * the compressed block if compression worked and the new block is
+ * actually smaller. Decompress using #GNUNET_decompress().
+ *
+ * @param data block to compress; if compression
+ * resulted in a smaller block, the first
+ * bytes of data are updated to the compressed
+ * data
+ * @param old_size number of bytes in data
+ * @param[out] result set to the compressed data, if compression worked
+ * @param[out] new_size set to size of result, if compression worked
+ * @return #GNUNET_YES if compression reduce the size,
+ * #GNUNET_NO if compression did not help
+ */
+int
+GNUNET_try_compression (const char *data,
+ size_t old_size,
+ char **result,
+ size_t *new_size);
+/**
+ * Decompress input, return the decompressed data as output. Dual to
+ * #GNUNET_try_compression(). Caller must set @a output_size to the
+ * number of bytes that were originally compressed.
+ *
+ * @param input compressed data
+ * @param input_size number of bytes in input
+ * @param output_size expected size of the output
+ * @return NULL on error, buffer of @a output_size decompressed bytes otherwise
+ */
+char *
+GNUNET_decompress (const char *input,
+ size_t input_size,
+ size_t output_size);
+
+
+#if HAVE_EXTRACTOR_H
+
+#include <extractor.h>
#else
void *value);
+/**
+ * Hash map from peer identities to values.
+ */
struct GNUNET_CONTAINER_MultiPeerMap;
+
+
/**
* @ingroup hashmap
* Create a multi peer map (hash map for public keys of peers).
void *it_cls);
+/* ***************** Version of Multihashmap for short hashes ****************** */
+
+/**
+ * @ingroup hashmap
+ * Iterator over hash map entries.
+ *
+ * @param cls closure
+ * @param key current public key
+ * @param value value in the hash map
+ * @return #GNUNET_YES if we should continue to
+ * iterate,
+ * #GNUNET_NO if not.
+ */
+typedef int
+(*GNUNET_CONTAINER_ShortmapIterator) (void *cls,
+ const struct GNUNET_ShortHashCode *key,
+ void *value);
+
+
+/**
+ * Hash map from peer identities to values.
+ */
+struct GNUNET_CONTAINER_MultiShortmap;
+
+
+/**
+ * @ingroup hashmap
+ * Create a multi peer map (hash map for public keys of peers).
+ *
+ * @param len initial size (map will grow as needed)
+ * @param do_not_copy_keys #GNUNET_NO is always safe and should be used by default;
+ * #GNUNET_YES means that on 'put', the 'key' does not have
+ * to be copied as the destination of the pointer is
+ * guaranteed to be life as long as the value is stored in
+ * the hashmap. This can significantly reduce memory
+ * consumption, but of course is also a recipie for
+ * heap corruption if the assumption is not true. Only
+ * use this if (1) memory use is important in this case and
+ * (2) you have triple-checked that the invariant holds
+ * @return NULL on error
+ */
+struct GNUNET_CONTAINER_MultiShortmap *
+GNUNET_CONTAINER_multishortmap_create (unsigned int len,
+ int do_not_copy_keys);
+
+
+/**
+ * @ingroup hashmap
+ * Destroy a hash map. Will not free any values
+ * stored in the hash map!
+ *
+ * @param map the map
+ */
+void
+GNUNET_CONTAINER_multishortmap_destroy (struct GNUNET_CONTAINER_MultiShortmap *map);
+
+
+/**
+ * @ingroup hashmap
+ * Given a key find a value in the map matching the key.
+ *
+ * @param map the map
+ * @param key what to look for
+ * @return NULL if no value was found; note that
+ * this is indistinguishable from values that just
+ * happen to be NULL; use "contains" to test for
+ * key-value pairs with value NULL
+ */
+void *
+GNUNET_CONTAINER_multishortmap_get (const struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode *key);
+
+
+/**
+ * @ingroup hashmap
+ * Remove the given key-value pair from the map. Note that if the
+ * key-value pair is in the map multiple times, only one of the pairs
+ * will be removed.
+ *
+ * @param map the map
+ * @param key key of the key-value pair
+ * @param value value of the key-value pair
+ * @return #GNUNET_YES on success, #GNUNET_NO if the key-value pair
+ * is not in the map
+ */
+int
+GNUNET_CONTAINER_multishortmap_remove (struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode * key,
+ const void *value);
+
+/**
+ * @ingroup hashmap
+ * Remove all entries for the given key from the map.
+ * Note that the values would not be "freed".
+ *
+ * @param map the map
+ * @param key identifies values to be removed
+ * @return number of values removed
+ */
+int
+GNUNET_CONTAINER_multishortmap_remove_all (struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode *key);
+
+
+/**
+ * @ingroup hashmap
+ * Check if the map contains any value under the given
+ * key (including values that are NULL).
+ *
+ * @param map the map
+ * @param key the key to test if a value exists for it
+ * @return #GNUNET_YES if such a value exists,
+ * #GNUNET_NO if not
+ */
+int
+GNUNET_CONTAINER_multishortmap_contains (const struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode *key);
+
+
+/**
+ * @ingroup hashmap
+ * Check if the map contains the given value under the given
+ * key.
+ *
+ * @param map the map
+ * @param key the key to test if a value exists for it
+ * @param value value to test for
+ * @return #GNUNET_YES if such a value exists,
+ * #GNUNET_NO if not
+ */
+int
+GNUNET_CONTAINER_multishortmap_contains_value (const struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode * key,
+ const void *value);
+
+
+/**
+ * @ingroup hashmap
+ * Store a key-value pair in the map.
+ *
+ * @param map the map
+ * @param key key to use
+ * @param value value to use
+ * @param opt options for put
+ * @return #GNUNET_OK on success,
+ * #GNUNET_NO if a value was replaced (with REPLACE)
+ * #GNUNET_SYSERR if #GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY was the option and the
+ * value already exists
+ */
+int
+GNUNET_CONTAINER_multishortmap_put (struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode *key,
+ void *value,
+ enum GNUNET_CONTAINER_MultiHashMapOption opt);
+
+
+/**
+ * @ingroup hashmap
+ * Get the number of key-value pairs in the map.
+ *
+ * @param map the map
+ * @return the number of key value pairs
+ */
+unsigned int
+GNUNET_CONTAINER_multishortmap_size (const struct GNUNET_CONTAINER_MultiShortmap *map);
+
+
+/**
+ * @ingroup hashmap
+ * Iterate over all entries in the map.
+ *
+ * @param map the map
+ * @param it function to call on each entry
+ * @param it_cls extra argument to @a it
+ * @return the number of key value pairs processed,
+ * #GNUNET_SYSERR if it aborted iteration
+ */
+int
+GNUNET_CONTAINER_multishortmap_iterate (const struct GNUNET_CONTAINER_MultiShortmap *map,
+ GNUNET_CONTAINER_ShortmapIterator it,
+ void *it_cls);
+
+
+struct GNUNET_CONTAINER_MultiShortmapIterator;
+
+
+/**
+ * @ingroup hashmap
+ * Create an iterator for a multihashmap.
+ * The iterator can be used to retrieve all the elements in the multihashmap
+ * one by one, without having to handle all elements at once (in contrast to
+ * #GNUNET_CONTAINER_multishortmap_iterate). Note that the iterator can not be
+ * used anymore if elements have been removed from @a map after the creation of
+ * the iterator, or 'map' has been destroyed. Adding elements to @a map may
+ * result in skipped or repeated elements.
+ *
+ * @param map the map to create an iterator for
+ * @return an iterator over the given multihashmap @a map
+ */
+struct GNUNET_CONTAINER_MultiShortmapIterator *
+GNUNET_CONTAINER_multishortmap_iterator_create (const struct GNUNET_CONTAINER_MultiShortmap *map);
+
+
+/**
+ * @ingroup hashmap
+ * Retrieve the next element from the hash map at the iterator's
+ * position. If there are no elements left, #GNUNET_NO is returned,
+ * and @a key and @a value are not modified. This operation is only
+ * allowed if no elements have been removed from the multihashmap
+ * since the creation of @a iter, and the map has not been destroyed.
+ * Adding elements may result in repeating or skipping elements.
+ *
+ * @param iter the iterator to get the next element from
+ * @param key pointer to store the key in, can be NULL
+ * @param value pointer to store the value in, can be NULL
+ * @return #GNUNET_YES we returned an element,
+ * #GNUNET_NO if we are out of elements
+ */
+int
+GNUNET_CONTAINER_multishortmap_iterator_next (struct GNUNET_CONTAINER_MultiShortmapIterator *iter,
+ struct GNUNET_ShortHashCode *key,
+ const void **value);
+
+
+/**
+ * @ingroup hashmap
+ * Destroy a multishortmap iterator.
+ *
+ * @param iter the iterator to destroy
+ */
+void
+GNUNET_CONTAINER_multishortmap_iterator_destroy (struct GNUNET_CONTAINER_MultiShortmapIterator *iter);
+
+
+/**
+ * @ingroup hashmap
+ * Iterate over all entries in the map that match a particular key.
+ *
+ * @param map the map
+ * @param key public key that the entries must correspond to
+ * @param it function to call on each entry
+ * @param it_cls extra argument to @a it
+ * @return the number of key value pairs processed,
+ * #GNUNET_SYSERR if it aborted iteration
+ */
+int
+GNUNET_CONTAINER_multishortmap_get_multiple (const struct GNUNET_CONTAINER_MultiShortmap *map,
+ const struct GNUNET_ShortHashCode *key,
+ GNUNET_CONTAINER_ShortmapIterator it,
+ void *it_cls);
+
+
+/**
+ * @ingroup hashmap
+ * Call @a it on a random value from the map, or not at all
+ * if the map is empty. Note that this function has linear
+ * complexity (in the size of the map).
+ *
+ * @param map the map
+ * @param it function to call on a random entry
+ * @param it_cls extra argument to @a it
+ * @return the number of key value pairs processed, zero or one.
+ */
+unsigned int
+GNUNET_CONTAINER_multishortmap_get_random (const struct GNUNET_CONTAINER_MultiShortmap *map,
+ GNUNET_CONTAINER_ShortmapIterator it,
+ void *it_cls);
+
+
/* Version of multihashmap with 32 bit keys */
/**
+/**
+ * Insertion sort of @a element into DLL from @a head to @a tail
+ * sorted by @a comparator.
+ *
+ * @param TYPE element type of the elements, i.e. `struct ListElement`
+ * @param comparator function like memcmp() to compare elements; takes
+ * three arguments, the @a comparator_cls and two elements,
+ * returns an `int` (-1, 0 or 1)
+ * @param comparator_cls closure for @a comparator
+ * @param[in,out] head head of DLL
+ * @param[in,out] tail tail of DLL
+ * @param element element to insert
+ */
+#define GNUNET_CONTAINER_DLL_insert_sorted(TYPE,comparator,comparator_cls,head,tail,element) do { \
+ if ( (NULL == head) || \
+ (0 < comparator (comparator_cls, \
+ element, \
+ head)) ) \
+ { \
+ /* insert at head, element < head */ \
+ GNUNET_CONTAINER_DLL_insert (head, \
+ tail, \
+ element); \
+ } \
+ else \
+ { \
+ TYPE *pos; \
+ \
+ for (pos = head; \
+ NULL != pos; \
+ pos = pos->next) \
+ if (0 < \
+ comparator (comparator_cls, \
+ element, \
+ pos)) \
+ break; /* element < pos */ \
+ if (NULL == pos) /* => element > tail */ \
+ { \
+ GNUNET_CONTAINER_DLL_insert_tail (head, \
+ tail, \
+ element); \
+ } \
+ else /* prev < element < pos */ \
+ { \
+ GNUNET_CONTAINER_DLL_insert_after (head, \
+ tail, \
+ pos->prev, \
+ element); \
+ } \
+ } \
+} while (0)
+
+
/* ******************** Heap *************** */
* @return cost of the node
*/
GNUNET_CONTAINER_HeapCostType
-GNUNET_CONTAINER_heap_node_get_cost (const struct GNUNET_CONTAINER_HeapNode
- *node);
+GNUNET_CONTAINER_heap_node_get_cost (const struct GNUNET_CONTAINER_HeapNode *node);
+
/**
* @ingroup heap
* @ingroup heap
* Updates the cost of any node in the tree
*
- * @param heap heap to modify
* @param node node for which the cost is to be changed
* @param new_cost new cost for the node
*/
void
-GNUNET_CONTAINER_heap_update_cost (struct GNUNET_CONTAINER_Heap *heap,
- struct GNUNET_CONTAINER_HeapNode *node,
+GNUNET_CONTAINER_heap_update_cost (struct GNUNET_CONTAINER_HeapNode *node,
GNUNET_CONTAINER_HeapCostType new_cost);