rocksdb/db/write_batch_internal.h
Abhishek Kona 8055008909 GetUpdatesSince API to enable replication.
Summary:
How it works:
* GetUpdatesSince takes a SequenceNumber.
* A LogFile with the first SequenceNumber nearest and lesser than the requested Sequence Number is found.
* Seek in the logFile till the requested SeqNumber is found.
* Return an iterator which contains logic to return record's one by one.

Test Plan:
* Test case included to check the good code path.
* Will update with more test-cases.
* Feedback required on test-cases.

Reviewers: dhruba, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7119
2012-12-07 11:42:13 -08:00

51 lines
1.5 KiB
C++

// 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 "leveldb/types.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 seqeunce number for the start of this batch.
static SequenceNumber Sequence(const WriteBatch* batch);
// Store the specified number as the seqeunce 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_