ecency-mobile/ios/Pods/boost-for-react-native/boost/container/detail/next_capacity.hpp

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2.4 KiB
C++

//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2014-2015. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/libs/container for documentation.
//
//////////////////////////////////////////////////////////////////////////////
#ifndef BOOST_CONTAINER_DETAIL_NEXT_CAPACITY_HPP
#define BOOST_CONTAINER_DETAIL_NEXT_CAPACITY_HPP
#ifndef BOOST_CONFIG_HPP
# include <boost/config.hpp>
#endif
#if defined(BOOST_HAS_PRAGMA_ONCE)
# pragma once
#endif
// container
#include <boost/container/throw_exception.hpp>
// container/detail
#include <boost/container/detail/min_max.hpp>
namespace boost {
namespace container {
namespace container_detail {
enum NextCapacityOption { NextCapacityDouble, NextCapacity60Percent };
template<class SizeType, NextCapacityOption Option>
struct next_capacity_calculator;
template<class SizeType>
struct next_capacity_calculator<SizeType, NextCapacityDouble>
{
static SizeType get(const SizeType max_size
,const SizeType capacity
,const SizeType n)
{
const SizeType remaining = max_size - capacity;
if ( remaining < n )
boost::container::throw_length_error("get_next_capacity, allocator's max_size reached");
const SizeType additional = max_value(n, capacity);
return ( remaining < additional ) ? max_size : ( capacity + additional );
}
};
template<class SizeType>
struct next_capacity_calculator<SizeType, NextCapacity60Percent>
{
static SizeType get(const SizeType max_size
,const SizeType capacity
,const SizeType n)
{
const SizeType remaining = max_size - capacity;
if ( remaining < n )
boost::container::throw_length_error("get_next_capacity, allocator's max_size reached");
const SizeType m3 = max_size/3;
if (capacity < m3)
return capacity + max_value(3*(capacity+1)/5, n);
if (capacity < m3*2)
return capacity + max_value((capacity+1)/2, n);
return max_size;
}
};
} //namespace container_detail {
} //namespace container {
} //namespace boost {
#endif //#ifndef BOOST_CONTAINER_DETAIL_NEXT_CAPACITY_HPP