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/**
* Copyright (C) 2019-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 <vector>
namespace mongo {
namespace container_size_helper {
/**
* Returns the estimate of the number of bytes consumed by the vector, based on the current capacity
* of the vector and the size of objects of type T. Does not incorporate the size of any owned
* objects that are pointed to by T. Also, does not incorporate sizeof(vector).
*/
template <class T>
uint64_t estimateObjectSizeInBytes(const std::vector<T>& vector) {
return static_cast<uint64_t>(vector.capacity()) * sizeof(T);
}
/**
* Returns the estimate of the number of bytes consumed by the container, based on the current
* capacity of the container and the size of objects of type 'T::value_type'. Does not incorporate
* the size of any owned objects that are pointed to by 'T::value_type'. Also, does not incorporate
* sizeof(container).
*/
template <class T>
uint64_t estimateObjectSizeInBytes(const T& container) {
return static_cast<uint64_t>(container.size()) * sizeof(typename T::value_type);
}
/**
* Returns the estimate by recursively calculating the memory owned by each element of the
* container. The 'function' should calculate the overall size of each individual element of the
* 'container'.
* When 'includeShallowSize' is true, adds the size of each container element.
*/
template <class T, class Function>
uint64_t estimateObjectSizeInBytes(const T& container, Function function, bool includeShallowSize) {
uint64_t result = 0;
for (const auto& element : container) {
result += function(element);
}
result += includeShallowSize ? estimateObjectSizeInBytes(container) : 0;
return result;
}
} // namespace container_size_helper
} // namespace mongo
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