rocksdb/db/snapshot_checker.h
sdong 4720ba4391 Remove RocksDB LITE (#11147)
Summary:
We haven't been actively mantaining RocksDB LITE recently and the size must have been gone up significantly. We are removing the support.

Most of changes were done through following comments:

unifdef -m -UROCKSDB_LITE `git grep -l ROCKSDB_LITE | egrep '[.](cc|h)'`

by Peter Dillinger. Others changes were manually applied to build scripts, CircleCI manifests, ROCKSDB_LITE is used in an expression and file db_stress_test_base.cc.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11147

Test Plan: See CI

Reviewed By: pdillinger

Differential Revision: D42796341

fbshipit-source-id: 4920e15fc2060c2cd2221330a6d0e5e65d4b7fe2
2023-01-27 13:14:19 -08:00

59 lines
1.8 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).
#pragma once
#include "rocksdb/types.h"
namespace ROCKSDB_NAMESPACE {
enum class SnapshotCheckerResult : int {
kInSnapshot = 0,
kNotInSnapshot = 1,
// In case snapshot is released and the checker has no clue whether
// the given sequence is visible to the snapshot.
kSnapshotReleased = 2,
};
// Callback class that control GC of duplicate keys in flush/compaction.
class SnapshotChecker {
public:
virtual ~SnapshotChecker() {}
virtual SnapshotCheckerResult CheckInSnapshot(
SequenceNumber sequence, SequenceNumber snapshot_sequence) const = 0;
};
class DisableGCSnapshotChecker : public SnapshotChecker {
public:
virtual ~DisableGCSnapshotChecker() {}
virtual SnapshotCheckerResult CheckInSnapshot(
SequenceNumber /*sequence*/,
SequenceNumber /*snapshot_sequence*/) const override {
// By returning kNotInSnapshot, we prevent all the values from being GCed
return SnapshotCheckerResult::kNotInSnapshot;
}
static DisableGCSnapshotChecker* Instance();
protected:
explicit DisableGCSnapshotChecker() {}
};
class WritePreparedTxnDB;
// Callback class created by WritePreparedTxnDB to check if a key
// is visible by a snapshot.
class WritePreparedSnapshotChecker : public SnapshotChecker {
public:
explicit WritePreparedSnapshotChecker(WritePreparedTxnDB* txn_db);
virtual ~WritePreparedSnapshotChecker() {}
virtual SnapshotCheckerResult CheckInSnapshot(
SequenceNumber sequence, SequenceNumber snapshot_sequence) const override;
private:
const WritePreparedTxnDB* const txn_db_;
};
} // namespace ROCKSDB_NAMESPACE