libcruft-util/alloc/allocator.hpp
Danny Robson f6056153e3 rename root namespace from util to cruft
This places, at long last, the core library code into the same namespace
as the extended library code.
2018-08-05 14:42:02 +10:00

67 lines
1.6 KiB
C++

/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* Copyright 2015-2018 Danny Robson <danny@nerdcruft.net>
*/
#pragma once
#include "../view.hpp"
#include <cstddef>
#include <utility>
// C++11 allocator concept conformant(ish) allocator adaptor, going from our
// allocator interface to that of the STL and friends.
namespace cruft::alloc {
template <typename ValueT, typename BackingT>
class allocator {
public:
typedef ValueT value_type;
template <typename ...Args>
explicit allocator (Args&& ...args):
m_backing (std::forward<Args> (args)...)
{ ; }
cruft::view<ValueT*>
allocate (size_t count)
{
return {
reinterpret_cast<ValueT*> (
m_backing.template allocate (
sizeof (ValueT) * count,
alignof (ValueT)
)
),
count
};
}
void
deallocate (ValueT *t, size_t count)
{
return m_backing.template deallocate (t, sizeof (ValueT) * count);
}
private:
BackingT &m_backing;
};
///////////////////////////////////////////////////////////////////////////
// convenience type-inferring constructor for allocators.
template <typename ValueT, typename BackingT>
auto
make_allocator (BackingT &backing)
{
return allocator<ValueT,BackingT> (backing);
}
}