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-rw-r--r--src/rocksdb/table/cuckoo/cuckoo_table_factory.h82
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diff --git a/src/rocksdb/table/cuckoo/cuckoo_table_factory.h b/src/rocksdb/table/cuckoo/cuckoo_table_factory.h
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+++ b/src/rocksdb/table/cuckoo/cuckoo_table_factory.h
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+// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
+// This source code is licensed under both the GPLv2 (found in the
+// COPYING file in the root directory) and Apache 2.0 License
+// (found in the LICENSE.Apache file in the root directory).
+
+#pragma once
+#ifndef ROCKSDB_LITE
+
+#include <string>
+
+#include "rocksdb/options.h"
+#include "rocksdb/table.h"
+#include "util/murmurhash.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+const uint32_t kCuckooMurmurSeedMultiplier = 816922183;
+static inline uint64_t CuckooHash(
+ const Slice& user_key, uint32_t hash_cnt, bool use_module_hash,
+ uint64_t table_size_, bool identity_as_first_hash,
+ uint64_t (*get_slice_hash)(const Slice&, uint32_t, uint64_t)) {
+#if !defined NDEBUG || defined OS_WIN
+ // This part is used only in unit tests but we have to keep it for Windows
+ // build as we run test in both debug and release modes under Windows.
+ if (get_slice_hash != nullptr) {
+ return get_slice_hash(user_key, hash_cnt, table_size_);
+ }
+#else
+ (void)get_slice_hash;
+#endif
+
+ uint64_t value = 0;
+ if (hash_cnt == 0 && identity_as_first_hash) {
+ value = (*reinterpret_cast<const int64_t*>(user_key.data()));
+ } else {
+ value = MurmurHash(user_key.data(), static_cast<int>(user_key.size()),
+ kCuckooMurmurSeedMultiplier * hash_cnt);
+ }
+ if (use_module_hash) {
+ return value % table_size_;
+ } else {
+ return value & (table_size_ - 1);
+ }
+}
+
+// Cuckoo Table is designed for applications that require fast point lookups
+// but not fast range scans.
+//
+// Some assumptions:
+// - Key length and Value length are fixed.
+// - Does not support Snapshot.
+// - Does not support Merge operations.
+// - Does not support prefix bloom filters.
+class CuckooTableFactory : public TableFactory {
+ public:
+ explicit CuckooTableFactory(
+ const CuckooTableOptions& table_option = CuckooTableOptions());
+ ~CuckooTableFactory() {}
+
+ // Method to allow CheckedCast to work for this class
+ static const char* kClassName() { return kCuckooTableName(); }
+ const char* Name() const override { return kCuckooTableName(); }
+
+ using TableFactory::NewTableReader;
+ Status NewTableReader(
+ const ReadOptions& ro, const TableReaderOptions& table_reader_options,
+ std::unique_ptr<RandomAccessFileReader>&& file, uint64_t file_size,
+ std::unique_ptr<TableReader>* table,
+ bool prefetch_index_and_filter_in_cache = true) const override;
+
+ TableBuilder* NewTableBuilder(
+ const TableBuilderOptions& table_builder_options,
+ WritableFileWriter* file) const override;
+
+ std::string GetPrintableOptions() const override;
+
+ private:
+ CuckooTableOptions table_options_;
+};
+
+} // namespace ROCKSDB_NAMESPACE
+#endif // ROCKSDB_LITE