*/
/**
* @file util/container_multihashmap.c
- * @brief hash map where the same key maybe present multiple times
+ * @brief hash map where the same key may be present multiple times
* @author Christian Grothoff
*/
#include "gnunet_container_lib.h"
#include "gnunet_crypto_lib.h"
+/**
+ * An entry in the hash map.
+ */
struct MapEntry
{
+
+ /**
+ * Key for the entry.
+ */
GNUNET_HashCode key;
+
+ /**
+ * Value of the entry.
+ */
void *value;
+
+ /**
+ * If there is a hash collision, we create a linked list.
+ */
struct MapEntry *next;
+
};
+/**
+ * Internal representation of the hash map.
+ */
struct GNUNET_CONTAINER_MultiHashMap
{
+ /**
+ * All of our buckets.
+ */
struct MapEntry **map;
+ /**
+ * Number of entries in the map.
+ */
unsigned int size;
+ /**
+ * Length of the "map" array.
+ */
unsigned int map_length;
};
+
+/**
+ * Create a multi hash map.
+ *
+ * @param len initial size (map will grow as needed)
+ * @return NULL on error
+ */
struct GNUNET_CONTAINER_MultiHashMap *
GNUNET_CONTAINER_multihashmap_create (unsigned int len)
{
struct GNUNET_CONTAINER_MultiHashMap *ret;
+ GNUNET_assert (len > 0);
ret = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_MultiHashMap));
- ret->size = 0;
ret->map = GNUNET_malloc (len * sizeof (struct MapEntry *));
- memset (ret->map, 0, len * sizeof (struct MapEntry *));
ret->map_length = len;
return ret;
}
+
+/**
+ * Destroy a hash map. Will not free any values
+ * stored in the hash map!
+ *
+ * @param map the map
+ */
void
GNUNET_CONTAINER_multihashmap_destroy (struct GNUNET_CONTAINER_MultiHashMap
*map)
struct MapEntry *e;
for (i = 0; i < map->map_length; i++)
+ {
+ while (NULL != (e = map->map[i]))
{
- while (NULL != (e = map->map[i]))
- {
- map->map[i] = e->next;
- GNUNET_free (e);
- }
+ map->map[i] = e->next;
+ GNUNET_free (e);
}
+ }
GNUNET_free (map->map);
GNUNET_free (map);
}
+
+/**
+ * Compute the index of the bucket for the given key.
+ *
+ * @param m hash map for which to compute the index
+ * @param key what key should the index be computed for
+ * @return offset into the "map" array of "m"
+ */
static unsigned int
idx_of (const struct GNUNET_CONTAINER_MultiHashMap *m,
const GNUNET_HashCode * key)
{
+ GNUNET_assert (m != NULL);
return (*(unsigned int *) key) % m->map_length;
}
+
+/**
+ * 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_multihashmap_size (const struct GNUNET_CONTAINER_MultiHashMap
*map)
return map->size;
}
+
+/**
+ * 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_multihashmap_get (const struct GNUNET_CONTAINER_MultiHashMap
*map, const GNUNET_HashCode * key)
e = map->map[idx_of (map, key)];
while (e != NULL)
- {
- if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
- return e->value;
- e = e->next;
- }
+ {
+ if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
+ return e->value;
+ e = e->next;
+ }
return NULL;
}
+
+/**
+ * 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 it
+ * @return the number of key value pairs processed,
+ * GNUNET_SYSERR if it aborted iteration
+ */
int
GNUNET_CONTAINER_multihashmap_iterate (const struct
GNUNET_CONTAINER_MultiHashMap *map,
GNUNET_CONTAINER_HashMapIterator it,
- void *cls)
+ void *it_cls)
{
int count;
unsigned int i;
struct MapEntry *e;
+ struct MapEntry *n;
+ GNUNET_HashCode kc;
count = 0;
+ GNUNET_assert (map != NULL);
for (i = 0; i < map->map_length; i++)
+ {
+ n = map->map[i];
+ while (NULL != (e = n))
{
- e = map->map[i];
- while (e != NULL)
- {
- if ((NULL != it) && (GNUNET_OK != it (&e->key, e->value, cls)))
- return GNUNET_SYSERR;
- count++;
- e = e->next;
- }
+ n = e->next;
+ if (NULL != it)
+ {
+ kc = e->key;
+ if (GNUNET_OK != it (it_cls, &kc, e->value))
+ return GNUNET_SYSERR;
+ }
+ count++;
}
+ }
return count;
}
+
+/**
+ * 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_multihashmap_remove (struct GNUNET_CONTAINER_MultiHashMap
*map, const GNUNET_HashCode * key,
p = NULL;
e = map->map[i];
while (e != NULL)
+ {
+ if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
+ (value == e->value))
{
- if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
- (value == e->value))
- {
- if (p == NULL)
- map->map[i] = e->next;
- else
- p->next = e->next;
- GNUNET_free (e);
- map->size--;
- return GNUNET_YES;
- }
- p = e;
- e = e->next;
+ if (p == NULL)
+ map->map[i] = e->next;
+ else
+ p->next = e->next;
+ GNUNET_free (e);
+ map->size--;
+ return GNUNET_YES;
}
+ p = e;
+ e = e->next;
+ }
return GNUNET_NO;
}
+
+/**
+ * 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_multihashmap_remove_all (struct GNUNET_CONTAINER_MultiHashMap
*map, const GNUNET_HashCode * key)
p = NULL;
e = map->map[i];
while (e != NULL)
+ {
+ if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
{
- if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
- {
- if (p == NULL)
- map->map[i] = e->next;
- else
- p->next = e->next;
- GNUNET_free (e);
- map->size--;
- if (p == NULL)
- e = map->map[i];
- else
- e = p->next;
- ret++;
- }
+ if (p == NULL)
+ map->map[i] = e->next;
+ else
+ p->next = e->next;
+ GNUNET_free (e);
+ map->size--;
+ if (p == NULL)
+ e = map->map[i];
else
- {
- p = e;
- e = e->next;
- }
+ e = p->next;
+ ret++;
+ }
+ else
+ {
+ p = e;
+ e = e->next;
}
+ }
return ret;
}
+
+/**
+ * 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_multihashmap_contains (const struct
GNUNET_CONTAINER_MultiHashMap *map,
const GNUNET_HashCode * key)
{
struct MapEntry *e;
- unsigned int i;
- i = idx_of (map, key);
- e = map->map[i];
+ e = map->map[idx_of (map, key)];
while (e != NULL)
- {
- if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
- return GNUNET_YES;
- e = e->next;
- }
+ {
+ if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
+ return GNUNET_YES;
+ e = e->next;
+ }
+ return GNUNET_NO;
+}
+
+
+/**
+ * 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_multihashmap_contains_value (const struct
+ GNUNET_CONTAINER_MultiHashMap
+ *map,
+ const GNUNET_HashCode * key,
+ const void *value)
+{
+ struct MapEntry *e;
+
+ e = map->map[idx_of (map, key)];
+ while (e != NULL)
+ {
+ if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
+ (e->value == value))
+ return GNUNET_YES;
+ e = e->next;
+ }
return GNUNET_NO;
}
+
+/**
+ * Grow the given map to a more appropriate size.
+ *
+ * @param map the hash map to grow
+ */
static void
grow (struct GNUNET_CONTAINER_MultiHashMap *map)
{
- struct MapEntry **old;
+ struct MapEntry **old_map;
+ struct MapEntry **new_map;
struct MapEntry *e;
+ unsigned int old_len;
+ unsigned int new_len;
+ unsigned int idx;
unsigned int i;
- unsigned int l;
-
- old = map->map;
- l = map->map_length;
- map->map_length *= 2;
- map->map = GNUNET_malloc (sizeof (struct MapEntry *) * map->map_length);
- memset (map->map, 0, sizeof (struct MapEntry *) * map->map_length);
- for (i = 0; i < l; i++)
+
+ old_map = map->map;
+ old_len = map->map_length;
+ new_len = old_len * 2;
+ new_map = GNUNET_malloc (sizeof (struct MapEntry *) * new_len);
+ map->map_length = new_len;
+ map->map = new_map;
+ for (i = 0; i < old_len; i++)
+ {
+ while (NULL != (e = old_map[i]))
{
- while (NULL != (e = old[i]))
- {
- old[i] = e->next;
- e->next = map->map[idx_of (map, &e->key)];
- map->map[idx_of (map, &e->key)] = e;
- }
+ old_map[i] = e->next;
+ idx = idx_of (map, &e->key);
+ e->next = new_map[idx];
+ new_map[idx] = e;
}
- GNUNET_free (old);
+ }
+ GNUNET_free (old_map);
}
+
+/**
+ * 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 UNIQUE_ONLY was the option and the
+ * value already exists
+ */
int
GNUNET_CONTAINER_multihashmap_put (struct GNUNET_CONTAINER_MultiHashMap *map,
const GNUNET_HashCode * key,
void *value,
- enum GNUNET_CONTAINER_MultiHashMapOption
- opt)
+ enum GNUNET_CONTAINER_MultiHashMapOption opt)
{
struct MapEntry *e;
unsigned int i;
i = idx_of (map, key);
if ((opt != GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE) &&
(opt != GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
+ {
+ e = map->map[i];
+ while (e != NULL)
{
- e = map->map[i];
- while (e != NULL)
- {
- if ((0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode))) &&
- (value == e->value))
- {
- if (opt == GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)
- return GNUNET_SYSERR;
- e->value = value;
- return GNUNET_NO;
- }
- e = e->next;
- }
+ if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
+ {
+ if (opt == GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)
+ return GNUNET_SYSERR;
+ e->value = value;
+ return GNUNET_NO;
+ }
+ e = e->next;
}
- if (map->size / 3 > map->map_length / 4)
+ }
+ if (map->size / 3 >= map->map_length / 4)
+ {
grow (map);
+ i = idx_of (map, key);
+ }
e = GNUNET_malloc (sizeof (struct MapEntry));
e->key = *key;
e->value = value;
return GNUNET_OK;
}
+
+/**
+ * Iterate over all entries in the map that match a particular key.
+ *
+ * @param map the map
+ * @param key key that the entries must correspond to
+ * @param it function to call on each entry
+ * @param it_cls extra argument to it
+ * @return the number of key value pairs processed,
+ * GNUNET_SYSERR if it aborted iteration
+ */
int
GNUNET_CONTAINER_multihashmap_get_multiple (const struct
GNUNET_CONTAINER_MultiHashMap
*map, const GNUNET_HashCode * key,
GNUNET_CONTAINER_HashMapIterator
- it, void *cls)
+ it, void *it_cls)
{
int count;
struct MapEntry *e;
+ struct MapEntry *n;
count = 0;
- e = map->map[idx_of (map, key)];
- while (e != NULL)
- {
- if (0 == memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
- {
- if ((it != NULL) && (GNUNET_OK != it (&e->key, e->value, cls)))
- return GNUNET_SYSERR;
- count++;
- }
- e = e->next;
- }
+ n = map->map[idx_of (map, key)];
+ while (NULL != (e = n))
+ {
+ n = e->next;
+ if (0 != memcmp (key, &e->key, sizeof (GNUNET_HashCode)))
+ continue;
+ if ((it != NULL) && (GNUNET_OK != it (it_cls, key, e->value)))
+ return GNUNET_SYSERR;
+ count++;
+ }
return count;
}
-void *
-GNUNET_CONTAINER_multihashmap_get_random (const struct
- GNUNET_CONTAINER_MultiHashMap *map)
-{
- unsigned int rand;
- struct MapEntry *e;
- e = NULL;
-
- if (map->size == 0)
- return NULL;
-
- while (e == NULL)
- {
- rand =
- GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
- map->map_length);
- e = map->map[rand];
- }
-
- return e->value;
-}
-/* end of multihashmap.c */
+/* end of container_multihashmap.c */
projects / oweals / gnunet.git / blobdiff