libcruft-util/alloc/stack.cpp

85 lines
1.7 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 2015-2016 Danny Robson <danny@nerdcruft.net>
*/
#include "stack.hpp"
#include "../debug/assert.hpp"
#include "../pointer.hpp"
#include "../cast.hpp"
using cruft::alloc::stack;
///////////////////////////////////////////////////////////////////////////////
stack::stack (cruft::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 ();
}