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+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// Thread-safe (provides internal synchronization)
+
+#ifndef STORAGE_LEVELDB_DB_TABLE_CACHE_H_
+#define STORAGE_LEVELDB_DB_TABLE_CACHE_H_
+
+#include <string>
+#include <stdint.h>
+#include "db/dbformat.h"
+#include "leveldb/cache.h"
+#include "leveldb/table.h"
+#include "port/port.h"
+
+namespace leveldb {
+
+class Env;
+
+class TableCache {
+ public:
+ TableCache(const std::string& dbname, const Options* options, int entries);
+ ~TableCache();
+
+ // Return an iterator for the specified file number (the corresponding
+ // file length must be exactly "file_size" bytes). If "tableptr" is
+ // non-NULL, also sets "*tableptr" to point to the Table object
+ // underlying the returned iterator, or NULL if no Table object underlies
+ // the returned iterator. The returned "*tableptr" object is owned by
+ // the cache and should not be deleted, and is valid for as long as the
+ // returned iterator is live.
+ Iterator* NewIterator(const ReadOptions& options,
+ uint64_t file_number,
+ uint64_t file_size,
+ Table** tableptr = NULL);
+
+ // If a seek to internal key "k" in specified file finds an entry,
+ // call (*handle_result)(arg, found_key, found_value).
+ Status Get(const ReadOptions& options,
+ uint64_t file_number,
+ uint64_t file_size,
+ const Slice& k,
+ void* arg,
+ void (*handle_result)(void*, const Slice&, const Slice&));
+
+ // Evict any entry for the specified file number
+ void Evict(uint64_t file_number);
+
+ private:
+ Env* const env_;
+ const std::string dbname_;
+ const Options* options_;
+ Cache* cache_;
+
+ Status FindTable(uint64_t file_number, uint64_t file_size, Cache::Handle**);
+};
+
+} // namespace leveldb
+
+#endif // STORAGE_LEVELDB_DB_TABLE_CACHE_H_