Merge branch 'master' of ssh://gnunet.org/gnunet

[oweals/gnunet.git] / src / include / gnunet_block_group_lib.h

diff --git a/src/include/gnunet_block_group_lib.h b/src/include/gnunet_block_group_lib.h
index 5fa14ce0042e1415772c54cdf1009115c4f8d6e6..3a3dfb2e27aada6e180b4d82da038f9f95d53c65 100644 (file)
--- a/src/include/gnunet_block_group_lib.h
+++ b/src/include/gnunet_block_group_lib.h
@@ -43,6 +43,24 @@ extern "C"
 #endif
 
 
+/**
+ * How many bytes should a bloomfilter be if we have already seen
+ * entry_count responses?  Sized so that do not have to
+ * re-size the filter too often (to keep it cheap).
+ *
+ * Since other peers will also add entries but not resize the filter,
+ * we should generally pick a slightly larger size than what the
+ * strict math would suggest.
+ *
+ * @param entry_count expected number of entries in the Bloom filter
+ * @param k number of bits set per entry
+ * @return must be a power of two and smaller or equal to 2^15.
+ */
+size_t
+GNUNET_BLOCK_GROUP_compute_bloomfilter_size (unsigned int entry_count,
+                                             unsigned int k);
+
+
 /**
  * Create a new block group that filters duplicates using a Bloom filter.
  *
@@ -66,6 +84,20 @@ GNUNET_BLOCK_GROUP_bf_create (void *cls,
                               size_t raw_data_size);
 
 
+/**
+ * Test if @a hc is contained in the Bloom filter of @a bg.  If so,
+ * return #GNUNET_YES.  If not, add @a hc to the Bloom filter and
+ * return #GNUNET_NO.
+ *
+ * @param bg block group to use for testing
+ * @param hc hash of element to evaluate
+ * @return #GNUNET_YES if @a hc is (likely) a duplicate
+ *         #GNUNET_NO if @a hc was definitively not in @bg (but now is)
+ */
+int
+GNUNET_BLOCK_GROUP_bf_test_and_set (struct GNUNET_BLOCK_Group *bg,
+                                    const struct GNUNET_HashCode *hc);
+
 
 #if 0                           /* keep Emacsens' auto-indent happy */
 {