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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.
*/
#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kStorage
#include "mongo/platform/basic.h"
#include <cstdio>
#include <fmt/format.h>
#include "mongo/db/storage/wiredtiger/wiredtiger_begin_transaction_block.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_util.h"
#include "mongo/util/errno_util.h"
namespace mongo {
using namespace fmt::literals;
WiredTigerBeginTxnBlock::WiredTigerBeginTxnBlock(
WT_SESSION* session,
PrepareConflictBehavior prepareConflictBehavior,
RoundUpPreparedTimestamps roundUpPreparedTimestamps,
RoundUpReadTimestamp roundUpReadTimestamp)
: _session(session) {
invariant(!_rollback);
str::stream builder;
if (prepareConflictBehavior == PrepareConflictBehavior::kIgnoreConflicts) {
builder << "ignore_prepare=true,";
} else if (prepareConflictBehavior == PrepareConflictBehavior::kIgnoreConflictsAllowWrites) {
builder << "ignore_prepare=force,";
}
if (roundUpPreparedTimestamps == RoundUpPreparedTimestamps::kRound ||
roundUpReadTimestamp == RoundUpReadTimestamp::kRound) {
builder << "roundup_timestamps=(";
if (roundUpPreparedTimestamps == RoundUpPreparedTimestamps::kRound) {
builder << "prepared=true,";
}
if (roundUpReadTimestamp == RoundUpReadTimestamp::kRound) {
builder << "read=true";
}
builder << "),";
}
if (roundUpReadTimestamp == RoundUpReadTimestamp::kNoRoundForce) {
builder << "read_before_oldest=true,";
}
const std::string beginTxnConfigString = builder;
invariantWTOK(_session->begin_transaction(_session, beginTxnConfigString.c_str()), _session);
_rollback = true;
}
WiredTigerBeginTxnBlock::WiredTigerBeginTxnBlock(WT_SESSION* session, const char* config)
: _session(session) {
invariant(!_rollback);
invariantWTOK(_session->begin_transaction(_session, config), _session);
_rollback = true;
}
WiredTigerBeginTxnBlock::~WiredTigerBeginTxnBlock() {
if (_rollback) {
invariant(_session->rollback_transaction(_session, nullptr) == 0);
}
}
Status WiredTigerBeginTxnBlock::setReadSnapshot(Timestamp readTimestamp) {
invariant(_rollback);
// Avoid heap allocation in favour of a stack allocation for the configuration string.
constexpr auto configFmtString = "read_timestamp={:x}";
constexpr auto numBytesRequired = std::char_traits<char>::length(configFmtString) +
(sizeof(decltype(readTimestamp.asULL())) * 2) + 1;
std::array<char, numBytesRequired> configString;
auto end =
fmt::format_to(configString.begin(), FMT_STRING(configFmtString), readTimestamp.asULL());
*end = '\0';
return wtRCToStatus(_session->timestamp_transaction(_session, configString.begin()), _session);
}
void WiredTigerBeginTxnBlock::done() {
invariant(_rollback);
_rollback = false;
}
} // namespace mongo
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