rocksdb/db/log_format.h
Yi Wu 48fc484950 Blob storage helper methods
Summary:
Split out interfaces needed for blob storage from #1560, including
* CompactionEventListener and OnFlushBegin listener interfaces.
* Blob filename support.
Closes https://github.com/facebook/rocksdb/pull/2169

Differential Revision: D4905463

Pulled By: yiwu-arbug

fbshipit-source-id: 564e73448f1b7a367e5e46216a521e57ea9011b5
2017-04-18 12:44:15 -07:00

46 lines
1.4 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
// 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.
//
// Log format information shared by reader and writer.
// See ../doc/log_format.txt for more detail.
#pragma once
namespace rocksdb {
namespace log {
enum RecordType {
// Zero is reserved for preallocated files
kZeroType = 0,
kFullType = 1,
// For fragments
kFirstType = 2,
kMiddleType = 3,
kLastType = 4,
// For recycled log files
kRecyclableFullType = 5,
kRecyclableFirstType = 6,
kRecyclableMiddleType = 7,
kRecyclableLastType = 8,
};
static const int kMaxRecordType = kRecyclableLastType;
static const unsigned int kBlockSize = 32768;
// Header is checksum (4 bytes), length (2 bytes), type (1 byte)
static const int kHeaderSize = 4 + 2 + 1;
// Recyclable header is checksum (4 bytes), type (1 byte), log number
// (4 bytes), length (2 bytes).
static const int kRecyclableHeaderSize = 4 + 1 + 4 + 2;
} // namespace log
} // namespace rocksdb