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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 <cstddef>
#include <vector>
#include <mongo/bson/timestamp.h>
#include <mongo/db/catalog/collection.h>
#include <mongo/db/namespace_string.h>
#include <mongo/db/operation_context.h>
#include <mongo/db/repl/oplog.h>
#include <mongo/db/service_context.h>
#include <mongo/stdx/mutex.h>
namespace mongo {
namespace repl {
/**
* This structure contains per-service-context state related to the oplog.
*/
class LocalOplogInfo {
public:
static LocalOplogInfo* get(ServiceContext& service);
static LocalOplogInfo* get(ServiceContext* service);
static LocalOplogInfo* get(OperationContext* opCtx);
LocalOplogInfo(const LocalOplogInfo&) = delete;
LocalOplogInfo& operator=(const LocalOplogInfo&) = delete;
LocalOplogInfo() = default;
/**
* Returns namespace of the local oplog collection.
*/
const NamespaceString& getOplogCollectionName() const;
/**
* Detects the current replication mode and sets the "_oplogName" accordingly.
*/
void setOplogCollectionName(ServiceContext* service);
Collection* getCollection() const;
void setCollection(Collection* oplog);
void resetCollection();
/**
* Sets the global Timestamp to be 'newTime'.
*/
void setNewTimestamp(ServiceContext* opCtx, const Timestamp& newTime);
/**
* Allocates optimes for new entries in the oplog. Returns the new optimes in a vector along
* with their terms.
*/
std::vector<OplogSlot> getNextOpTimes(OperationContext* opCtx, std::size_t count);
private:
// Name of the oplog collection.
NamespaceString _oplogName;
// The "oplog" pointer is always valid (or null) because an operation must take the global
// exclusive lock to set the pointer to null when the Collection instance is destroyed. See
// "oplogCheckCloseDatabase".
Collection* _oplog = nullptr;
// Synchronizes the section where a new Timestamp is generated and when it is registered in the
// storage engine.
mutable Mutex _newOpMutex = MONGO_MAKE_LATCH("LocaloplogInfo::_newOpMutex");
};
} // namespace repl
} // namespace mongo
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