From 587f21d8c0ec16f0812fd457b18cb29a9ed60229 Mon Sep 17 00:00:00 2001 From: Denis Kenzior Date: Sat, 9 Aug 2014 02:06:21 -0500 Subject: [PATCH] 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. --- src/libsystemd/sd-bus/bus-bloom.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/libsystemd/sd-bus/bus-bloom.c b/src/libsystemd/sd-bus/bus-bloom.c index e15429699..355677407 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; } -- 2.30.2