rocksdb/db/log_format.h
Yu Zhang 47235dda9e Add support in log writer and reader for a user-defined timestamp size record (#11433)
Summary:
This patch adds support to write and read a user-defined timestamp size record in log writer and log reader. It will be used by WAL logs to persist the user-defined timestamp format for subsequent WriteBatch records. Reading and writing UDT sizes for WAL logs are not included in this patch. It will be in a follow up.

The syntax for the record is: at write time, one such record is added when log writer encountered any non-zero UDT size it hasn't recorded so far. At read time, all such records read up to a point are accumulated and applicable to all subsequent WriteBatch records.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11433

Test Plan:
```
make clean && make -j32 all
./log_test --gtest_filter="*WithTimestampSize*"
```

Reviewed By: ltamasi

Differential Revision: D45678708

Pulled By: jowlyzhang

fbshipit-source-id: b770c8f45bb7b9383b14aac9f22af781304fb41d
2023-05-11 17:26:19 -07:00

56 lines
1.6 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root 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
#include "rocksdb/rocksdb_namespace.h"
namespace ROCKSDB_NAMESPACE {
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,
// Compression Type
kSetCompressionType = 9,
// User-defined timestamp sizes
kUserDefinedTimestampSizeType = 10,
kRecyclableUserDefinedTimestampSizeType = 11,
};
constexpr int kMaxRecordType = kRecyclableUserDefinedTimestampSizeType;
constexpr unsigned int kBlockSize = 32768;
// Header is checksum (4 bytes), length (2 bytes), type (1 byte)
constexpr int kHeaderSize = 4 + 2 + 1;
// Recyclable header is checksum (4 bytes), length (2 bytes), type (1 byte),
// log number (4 bytes).
constexpr int kRecyclableHeaderSize = 4 + 2 + 1 + 4;
} // namespace log
} // namespace ROCKSDB_NAMESPACE