1 // Copyright (c) 2012 The LevelDB 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. See the AUTHORS file for names of contributors.
5 #include "table/filter_block.h"
7 #include "leveldb/filter_policy.h"
8 #include "util/coding.h"
10 #include "util/logging.h"
11 #include "util/testharness.h"
12 #include "util/testutil.h"
16 // For testing: emit an array with one hash value per key
17 class TestHashFilter : public FilterPolicy {
19 virtual const char* Name() const {
20 return "TestHashFilter";
23 virtual void CreateFilter(const Slice* keys, int n, std::string* dst) const {
24 for (int i = 0; i < n; i++) {
25 uint32_t h = Hash(keys[i].data(), keys[i].size(), 1);
30 virtual bool KeyMayMatch(const Slice& key, const Slice& filter) const {
31 uint32_t h = Hash(key.data(), key.size(), 1);
32 for (size_t i = 0; i + 4 <= filter.size(); i += 4) {
33 if (h == DecodeFixed32(filter.data() + i)) {
41 class FilterBlockTest {
43 TestHashFilter policy_;
46 TEST(FilterBlockTest, EmptyBuilder) {
47 FilterBlockBuilder builder(&policy_);
48 Slice block = builder.Finish();
49 ASSERT_EQ("\\x00\\x00\\x00\\x00\\x0b", EscapeString(block));
50 FilterBlockReader reader(&policy_, block);
51 ASSERT_TRUE(reader.KeyMayMatch(0, "foo"));
52 ASSERT_TRUE(reader.KeyMayMatch(100000, "foo"));
55 TEST(FilterBlockTest, SingleChunk) {
56 FilterBlockBuilder builder(&policy_);
57 builder.StartBlock(100);
58 builder.AddKey("foo");
59 builder.AddKey("bar");
60 builder.AddKey("box");
61 builder.StartBlock(200);
62 builder.AddKey("box");
63 builder.StartBlock(300);
64 builder.AddKey("hello");
65 Slice block = builder.Finish();
66 FilterBlockReader reader(&policy_, block);
67 ASSERT_TRUE(reader.KeyMayMatch(100, "foo"));
68 ASSERT_TRUE(reader.KeyMayMatch(100, "bar"));
69 ASSERT_TRUE(reader.KeyMayMatch(100, "box"));
70 ASSERT_TRUE(reader.KeyMayMatch(100, "hello"));
71 ASSERT_TRUE(reader.KeyMayMatch(100, "foo"));
72 ASSERT_TRUE(! reader.KeyMayMatch(100, "missing"));
73 ASSERT_TRUE(! reader.KeyMayMatch(100, "other"));
76 TEST(FilterBlockTest, MultiChunk) {
77 FilterBlockBuilder builder(&policy_);
80 builder.StartBlock(0);
81 builder.AddKey("foo");
82 builder.StartBlock(2000);
83 builder.AddKey("bar");
86 builder.StartBlock(3100);
87 builder.AddKey("box");
89 // Third filter is empty
92 builder.StartBlock(9000);
93 builder.AddKey("box");
94 builder.AddKey("hello");
96 Slice block = builder.Finish();
97 FilterBlockReader reader(&policy_, block);
100 ASSERT_TRUE(reader.KeyMayMatch(0, "foo"));
101 ASSERT_TRUE(reader.KeyMayMatch(2000, "bar"));
102 ASSERT_TRUE(! reader.KeyMayMatch(0, "box"));
103 ASSERT_TRUE(! reader.KeyMayMatch(0, "hello"));
105 // Check second filter
106 ASSERT_TRUE(reader.KeyMayMatch(3100, "box"));
107 ASSERT_TRUE(! reader.KeyMayMatch(3100, "foo"));
108 ASSERT_TRUE(! reader.KeyMayMatch(3100, "bar"));
109 ASSERT_TRUE(! reader.KeyMayMatch(3100, "hello"));
111 // Check third filter (empty)
112 ASSERT_TRUE(! reader.KeyMayMatch(4100, "foo"));
113 ASSERT_TRUE(! reader.KeyMayMatch(4100, "bar"));
114 ASSERT_TRUE(! reader.KeyMayMatch(4100, "box"));
115 ASSERT_TRUE(! reader.KeyMayMatch(4100, "hello"));
118 ASSERT_TRUE(reader.KeyMayMatch(9000, "box"));
119 ASSERT_TRUE(reader.KeyMayMatch(9000, "hello"));
120 ASSERT_TRUE(! reader.KeyMayMatch(9000, "foo"));
121 ASSERT_TRUE(! reader.KeyMayMatch(9000, "bar"));
124 } // namespace leveldb
126 int main(int argc, char** argv) {
127 return leveldb::test::RunAllTests();