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#       1                 :            : // Copyright (c) 2011 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.
#       4                 :            : 
#       5                 :            : #ifndef STORAGE_LEVELDB_TABLE_BLOCK_BUILDER_H_
#       6                 :            : #define STORAGE_LEVELDB_TABLE_BLOCK_BUILDER_H_
#       7                 :            : 
#       8                 :            : #include <stdint.h>
#       9                 :            : 
#      10                 :            : #include <vector>
#      11                 :            : 
#      12                 :            : #include "leveldb/slice.h"
#      13                 :            : 
#      14                 :            : namespace leveldb {
#      15                 :            : 
#      16                 :            : struct Options;
#      17                 :            : 
#      18                 :            : class BlockBuilder {
#      19                 :            :  public:
#      20                 :            :   explicit BlockBuilder(const Options* options);
#      21                 :            : 
#      22                 :            :   BlockBuilder(const BlockBuilder&) = delete;
#      23                 :            :   BlockBuilder& operator=(const BlockBuilder&) = delete;
#      24                 :            : 
#      25                 :            :   // Reset the contents as if the BlockBuilder was just constructed.
#      26                 :            :   void Reset();
#      27                 :            : 
#      28                 :            :   // REQUIRES: Finish() has not been called since the last call to Reset().
#      29                 :            :   // REQUIRES: key is larger than any previously added key
#      30                 :            :   void Add(const Slice& key, const Slice& value);
#      31                 :            : 
#      32                 :            :   // Finish building the block and return a slice that refers to the
#      33                 :            :   // block contents.  The returned slice will remain valid for the
#      34                 :            :   // lifetime of this builder or until Reset() is called.
#      35                 :            :   Slice Finish();
#      36                 :            : 
#      37                 :            :   // Returns an estimate of the current (uncompressed) size of the block
#      38                 :            :   // we are building.
#      39                 :            :   size_t CurrentSizeEstimate() const;
#      40                 :            : 
#      41                 :            :   // Return true iff no entries have been added since the last Reset()
#      42                 :       8221 :   bool empty() const { return buffer_.empty(); }
#      43                 :            : 
#      44                 :            :  private:
#      45                 :            :   const Options* options_;
#      46                 :            :   std::string buffer_;              // Destination buffer
#      47                 :            :   std::vector<uint32_t> restarts_;  // Restart points
#      48                 :            :   int counter_;                     // Number of entries emitted since restart
#      49                 :            :   bool finished_;                   // Has Finish() been called?
#      50                 :            :   std::string last_key_;
#      51                 :            : };
#      52                 :            : 
#      53                 :            : }  // namespace leveldb
#      54                 :            : 
#      55                 :            : #endif  // STORAGE_LEVELDB_TABLE_BLOCK_BUILDER_H_