OLD | NEW |
---|---|
(Empty) | |
1 // Copyright 2014 The Chromium Authors. All rights reserved. | |
2 // Use of this source code is governed by a BSD-style license that can be | |
3 // found in the LICENSE file. | |
4 | |
5 #include "components/rappor/bloom_filter.h" | |
6 | |
7 #include "base/logging.h" | |
8 #include "third_party/smhasher/src/City.h" | |
9 | |
10 namespace rappor { | |
11 | |
12 BloomFilter::BloomFilter(uint32_t bytes_size, | |
13 uint32_t hash_function_count, | |
14 uint32_t hash_seed_offset) | |
15 : bytes_(bytes_size), | |
16 hash_function_count_(hash_function_count), | |
17 hash_seed_offset_(hash_seed_offset) { | |
18 DCHECK_GT(bytes_size, 0u); | |
19 } | |
20 | |
21 BloomFilter::~BloomFilter() {} | |
22 | |
23 void BloomFilter::AddString(const std::string& str) { | |
24 for (size_t i = 0; i < hash_function_count_; ++i) { | |
25 uint32_t index = | |
26 CityHash64WithSeed(str.data(), str.size(), hash_seed_offset_ + i); | |
Ilya Sherman
2014/02/13 01:39:03
Please document why CityHash is used here, rather
Steven Holte
2014/02/13 05:11:12
Added a comment which says "because it's supported
| |
27 // Note that the "bytes" are uint8_t, so they are always 8-bits. | |
28 uint32_t byte_index = (index / 8) % bytes_.size(); | |
29 uint32_t bit_index = index % 8; | |
30 bytes_[byte_index] |= 1 << bit_index; | |
31 } | |
32 } | |
33 | |
34 } // namespace rappor | |
OLD | NEW |