summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDenis Kenzior <denkenz@gmail.com>2014-08-09 02:06:21 -0500
committerLennart Poettering <lennart@poettering.net>2014-08-13 16:24:59 +0200
commit587f21d8c0ec16f0812fd457b18cb29a9ed60229 (patch)
treec70b97e4d0aa46368d5c7a8f4a6d6ec366891947
parentdae1e55b54800d6c5a0be8beab909f90ff5c3c72 (diff)
bus-bloom: Fix bloom filter calculation
i is being used incorrectly. It is used to refer to the number of indexes calculated so far (out of k). However, it is also incremented when a new hash key is being used. This means that the results are inconsistent with the desired behavior described in PORTING-DBUS1 document. The expected result is that for the default values of m and k (512, 8) the 1st hash key should produce 4 indexes. The second hash key is used for the next 4 and overall 8 indexes into m are calculated. The current behavior results in 6 indexes being calculated, 4 coming from hash key 1 and 2 others from hash key 5.
-rw-r--r--src/libsystemd/sd-bus/bus-bloom.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/src/libsystemd/sd-bus/bus-bloom.c b/src/libsystemd/sd-bus/bus-bloom.c
index e154296994..3556774074 100644
--- a/src/libsystemd/sd-bus/bus-bloom.c
+++ b/src/libsystemd/sd-bus/bus-bloom.c
@@ -48,6 +48,7 @@ static void bloom_add_data(
uint8_t h[8];
uint64_t m;
unsigned w, i, c = 0;
+ unsigned hash_index;
assert(size > 0);
assert(k > 0);
@@ -65,13 +66,13 @@ static void bloom_add_data(
* hash value for each 128 bits of hash key. */
assert(k * w <= ELEMENTSOF(hash_keys) * 8);
- for (i = 0; i < k; i++) {
+ for (i = 0, hash_index = 0; i < k; i++) {
uint64_t p = 0;
unsigned d;
for (d = 0; d < w; d++) {
if (c <= 0) {
- siphash24(h, data, n, hash_keys[i++].bytes);
+ siphash24(h, data, n, hash_keys[hash_index++].bytes);
c += 8;
}