/*
This file is part of GNUnet
- (C) 2012 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2012 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
- by the Free Software Foundation; either version 2, or (at your
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
*/
/**
- * @file consensus/ibf.c
+ * @file set/ibf.c
* @brief implementation of the invertible bloom filter
* @author Florian Dold
*/
#include "ibf.h"
+/**
+ * Compute the key's hash from the key.
+ * Redefine to use a different hash function.
+ */
+#define IBF_KEY_HASH_VAL(k) (GNUNET_CRYPTO_crc32_n (&(k), sizeof (struct IBF_KeyHash)))
+
/**
* Create a key from a hashcode.
*
struct IBF_Key
ibf_key_from_hashcode (const struct GNUNET_HashCode *hash)
{
- /* FIXME: endianess */
return *(struct IBF_Key *) hash;
}
* @param dst hashcode to store the result in
*/
void
-ibf_hashcode_from_key (struct IBF_Key key, struct GNUNET_HashCode *dst)
+ibf_hashcode_from_key (struct IBF_Key key,
+ struct GNUNET_HashCode *dst)
{
struct IBF_Key *p;
unsigned int i;
const unsigned int keys_per_hashcode = sizeof (struct GNUNET_HashCode) / sizeof (struct IBF_Key);
+
p = (struct IBF_Key *) dst;
for (i = 0; i < keys_per_hashcode; i++)
*p++ = key;
*
* @param size number of IBF buckets
* @param hash_num number of buckets one element is hashed in
- * @return the newly created invertible bloom filter
+ * @return the newly created invertible bloom filter, NULL on error
*/
struct InvertibleBloomFilter *
ibf_create (uint32_t size, uint8_t hash_num)
{
struct InvertibleBloomFilter *ibf;
- /* TODO: use malloc_large */
+ GNUNET_assert (0 != size);
- ibf = GNUNET_malloc (sizeof (struct InvertibleBloomFilter));
- ibf->count = GNUNET_malloc (size * sizeof (uint8_t));
- ibf->key_sum = GNUNET_malloc (size * sizeof (struct GNUNET_HashCode));
- ibf->key_hash_sum = GNUNET_malloc (size * sizeof (struct GNUNET_HashCode));
+ ibf = GNUNET_new (struct InvertibleBloomFilter);
+ ibf->count = GNUNET_malloc_large (size * sizeof (uint8_t));
+ if (NULL == ibf->count)
+ {
+ GNUNET_free (ibf);
+ return NULL;
+ }
+ ibf->key_sum = GNUNET_malloc_large (size * sizeof (struct IBF_Key));
+ if (NULL == ibf->key_sum)
+ {
+ GNUNET_free (ibf->count);
+ GNUNET_free (ibf);
+ return NULL;
+ }
+ ibf->key_hash_sum = GNUNET_malloc_large (size * sizeof (struct IBF_KeyHash));
+ if (NULL == ibf->key_hash_sum)
+ {
+ GNUNET_free (ibf->key_sum);
+ GNUNET_free (ibf->count);
+ GNUNET_free (ibf);
+ return NULL;
+ }
ibf->size = size;
ibf->hash_num = hash_num;
return ibf;
}
+
/**
* Store unique bucket indices for the specified key in dst.
*/
-static inline void
+static void
ibf_get_indices (const struct InvertibleBloomFilter *ibf,
- struct IBF_Key key, int *dst)
+ struct IBF_Key key,
+ int *dst)
{
- struct GNUNET_HashCode bucket_indices;
- unsigned int filled;
- int i;
- GNUNET_CRYPTO_hash (&key, sizeof key, &bucket_indices);
- filled = 0;
- for (i = 0; filled < ibf->hash_num; i++)
+ uint32_t filled;
+ uint32_t i;
+ uint32_t bucket;
+
+ bucket = GNUNET_CRYPTO_crc32_n (&key, sizeof key);
+ for (i = 0, filled=0; filled < ibf->hash_num; i++)
{
- unsigned int bucket;
unsigned int j;
- if ( (0 != i) && (0 == (i % 16)) )
- GNUNET_CRYPTO_hash (&bucket_indices, sizeof (struct GNUNET_HashCode), &bucket_indices);
- bucket = bucket_indices.bits[i % 16] % ibf->size;
+ uint64_t x;
for (j = 0; j < filled; j++)
if (dst[j] == bucket)
goto try_next;
- dst[filled++] = bucket;
+ dst[filled++] = bucket % ibf->size;
try_next: ;
+ x = ((uint64_t) bucket << 32) | i;
+ bucket = GNUNET_CRYPTO_crc32_n (&x, sizeof x);
}
}
const int *buckets, int side)
{
int i;
- struct GNUNET_HashCode key_hash_sha;
- struct IBF_KeyHash key_hash;
- GNUNET_CRYPTO_hash (&key, sizeof key, &key_hash_sha);
- key_hash.key_hash_val = key_hash_sha.bits[0];
+
for (i = 0; i < ibf->hash_num; i++)
{
const int bucket = buckets[i];
ibf->count[bucket].count_val += side;
ibf->key_sum[bucket].key_val ^= key.key_val;
- ibf->key_hash_sum[bucket].key_hash_val ^= key_hash.key_hash_val;
+ ibf->key_hash_sum[bucket].key_hash_val
+ ^= IBF_KEY_HASH_VAL (key);
}
}
/**
- * Insert an element into an IBF.
+ * Insert a key into an IBF.
*
* @param ibf the IBF
* @param key the element's hash code
ibf_insert_into (ibf, key, buckets, 1);
}
+
+/**
+ * Remove a key from an IBF.
+ *
+ * @param ibf the IBF
+ * @param key the element's hash code
+ */
+void
+ibf_remove (struct InvertibleBloomFilter *ibf, struct IBF_Key key)
+{
+ int buckets[ibf->hash_num];
+ GNUNET_assert (ibf->hash_num <= ibf->size);
+ ibf_get_indices (ibf, key, buckets);
+ ibf_insert_into (ibf, key, buckets, -1);
+}
+
+
/**
* Test is the IBF is empty, i.e. all counts, keys and key hashes are zero.
*/
{
struct IBF_KeyHash hash;
int i;
- struct GNUNET_HashCode key_hash_sha;
int buckets[ibf->hash_num];
GNUNET_assert (NULL != ibf);
if ((1 != ibf->count[i].count_val) && (-1 != ibf->count[i].count_val))
continue;
- GNUNET_CRYPTO_hash (&ibf->key_sum[i], sizeof (struct IBF_Key), &key_hash_sha);
- hash.key_hash_val = key_hash_sha.bits[0];
+ hash.key_hash_val = IBF_KEY_HASH_VAL (ibf->key_sum[i]);
/* test if the hash matches the key */
if (hash.key_hash_val != ibf->key_hash_sum[i].key_hash_val)
/**
* Write buckets from an ibf to a buffer.
* Exactly (IBF_BUCKET_SIZE*ibf->size) bytes are written to buf.
- *
+ *
* @param ibf the ibf to write
* @param start with which bucket to start
* @param count how many buckets to write
/* copy keys */
key_dst = (struct IBF_Key *) buf;
- memcpy (key_dst, ibf->key_sum + start, count * sizeof *key_dst);
+ GNUNET_memcpy (key_dst, ibf->key_sum + start, count * sizeof *key_dst);
key_dst += count;
/* copy key hashes */
key_hash_dst = (struct IBF_KeyHash *) key_dst;
- memcpy (key_hash_dst, ibf->key_hash_sum + start, count * sizeof *key_hash_dst);
+ GNUNET_memcpy (key_hash_dst, ibf->key_hash_sum + start, count * sizeof *key_hash_dst);
key_hash_dst += count;
/* copy counts */
count_dst = (struct IBF_Count *) key_hash_dst;
- memcpy (count_dst, ibf->count + start, count * sizeof *count_dst);
- count_dst += count;
+ GNUNET_memcpy (count_dst, ibf->count + start, count * sizeof *count_dst);
}
struct IBF_KeyHash *key_hash_src;
struct IBF_Count *count_src;
+ GNUNET_assert (count > 0);
GNUNET_assert (start + count <= ibf->size);
/* copy keys */
key_src = (struct IBF_Key *) buf;
- memcpy (ibf->key_sum + start, key_src, count * sizeof *key_src);
+ GNUNET_memcpy (ibf->key_sum + start, key_src, count * sizeof *key_src);
key_src += count;
/* copy key hashes */
key_hash_src = (struct IBF_KeyHash *) key_src;
- memcpy (ibf->key_hash_sum + start, key_hash_src, count * sizeof *key_hash_src);
+ GNUNET_memcpy (ibf->key_hash_sum + start, key_hash_src, count * sizeof *key_hash_src);
key_hash_src += count;
/* copy counts */
count_src = (struct IBF_Count *) key_hash_src;
- memcpy (ibf->count + start, count_src, count * sizeof *count_src);
- count_src += count;
+ GNUNET_memcpy (ibf->count + start, count_src, count * sizeof *count_src);
}
GNUNET_free (ibf->count);
GNUNET_free (ibf);
}
-