libcruft-util/alloc/raw/stack.cpp

93 lines
2.1 KiB
C++

/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Copyright 2015-2016 Danny Robson <danny@nerdcruft.net>
*/
#include "stack.hpp"
#include "../../debug.hpp"
#include "../../pointer.hpp"
#include "../../cast.hpp"
using util::alloc::raw::stack;
///////////////////////////////////////////////////////////////////////////////
stack::stack (util::view<std::byte*> _data):
m_begin (_data.begin ()),
m_end (_data.end ()),
m_cursor (m_begin)
{
CHECK_LE (m_begin, m_end);
}
//-----------------------------------------------------------------------------
std::byte*
stack::begin (void)
{
return m_begin;
}
//-----------------------------------------------------------------------------
const std::byte*
stack::begin (void) const
{
return m_begin;
}
//-----------------------------------------------------------------------------
size_t
stack::offset (const void *_ptr) const
{
auto ptr = reinterpret_cast<const std::byte*> (_ptr);
CHECK_GE (ptr, m_begin);
return ptr - m_begin;
}
//-----------------------------------------------------------------------------
void
stack::reset (void)
{
m_cursor = m_begin;
}
///////////////////////////////////////////////////////////////////////////////
size_t
stack::capacity (void) const
{
return m_end - m_begin;
}
//-----------------------------------------------------------------------------
size_t
stack::used (void) const
{
return m_cursor - m_begin;
}
//-----------------------------------------------------------------------------
size_t
stack::remain (void) const
{
return capacity () - used ();
}