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/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <string>
#include <wiredtiger.h>
#include "mongo/base/status.h"
#include "mongo/bson/timestamp.h"
namespace mongo {
/**
* When constructed, this object begins a WiredTiger transaction on the provided session. The
* transaction will be rolled back if done() is not called before the object is destructed.
*/
class WiredTigerBeginTxnBlock {
public:
// Whether or not to ignore prepared transactions.
enum class IgnorePrepared {
kNoIgnore, // Enforce prepare conflicts when encountering updates from prepared
// transactions.
kIgnore // Ignore prepare conflicts, but don't show prepared data.
};
// Whether or not to round up to the oldest timestamp when the read timestamp is behind it.
enum class RoundUpReadTimestamp {
kNoRound, // Do not round to the oldest timestamp. BadValue error may be returned.
kRound // Round the read timestamp up to the oldest timestamp when it is behind.
};
// Dictates whether to round up prepare and commit timestamp of a prepared transaction.
// 'kNoRound' - Does not round up prepare and commit timestamp of a prepared transaction.
// 'kRound' - The prepare timestamp will be rounded up to the oldest timestamp if found to be
// earlier; and the commit timestamp will be rounded up to the prepare timestamp if found to be
// earlier.
enum class RoundUpPreparedTimestamps { kNoRound, kRound };
WiredTigerBeginTxnBlock(
WT_SESSION* session,
IgnorePrepared ignorePrepared,
RoundUpPreparedTimestamps roundUpPreparedTimestamps,
RoundUpReadTimestamp roundUpReadTimestamp = RoundUpReadTimestamp::kNoRound);
WiredTigerBeginTxnBlock(WT_SESSION* session, const char* config);
~WiredTigerBeginTxnBlock();
/**
* Sets the read timestamp on the opened transaction. Cannot be called after a call to done().
*/
Status setReadSnapshot(Timestamp);
/**
* End the begin transaction block. Must be called to ensure the opened transaction
* is not be rolled back.
*/
void done();
private:
WT_SESSION* _session;
bool _rollback = false;
};
} // namespace mongo
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