// 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.

#ifndef STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_

#define STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_

#include "db/dbformat.h"

#include "leveldb/write_batch.h"

namespace leveldb {

class MemTable;

// WriteBatchInternal provides static methods for manipulating a

// WriteBatch that we don't want in the public WriteBatch interface.

class WriteBatchInternal {

 public:

  // Return the number of entries in the batch.

  static int Count(const WriteBatch* batch);

  // Set the count for the number of entries in the batch.

  static void SetCount(WriteBatch* batch, int n);

  // Return the sequence number for the start of this batch.

  static SequenceNumber Sequence(const WriteBatch* batch);

  // Store the specified number as the sequence number for the start of

  // this batch.

  static void SetSequence(WriteBatch* batch, SequenceNumber seq);

  static Slice Contents(const WriteBatch* batch) { return Slice(batch->rep_); }

  static size_t ByteSize(const WriteBatch* batch) { return batch->rep_.size(); }

  static void SetContents(WriteBatch* batch, const Slice& contents);

  static Status InsertInto(const WriteBatch* batch, MemTable* memtable);

  static void Append(WriteBatch* dst, const WriteBatch* src);

};

}  // namespace leveldb

#endif  // STORAGE_LEVELDB_DB_WRITE_BATCH_INTERNAL_H_