libcruft-util/alloc/raw/null.cpp
Danny Robson 7af076e2de alloc: prefer std::byte representations for iterators
this allows the users to more easily walk the byte ranges (or perform
simply pointer arithmetic), without as much danger of using the values
in an expression inadvertantly.
2018-02-28 17:55:56 +11:00

135 lines
2.9 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 Danny Robson <danny@nerdcruft.net>
*/
#include "null.hpp"
#include "../../debug.hpp"
#include <new>
using util::alloc::raw::null;
///////////////////////////////////////////////////////////////////////////////
void*
null::allocate (size_t bytes)
{
return allocate (bytes, alignof (std::max_align_t));
}
//-----------------------------------------------------------------------------
void*
null::allocate (size_t bytes, size_t align)
{
(void)bytes;
(void)align;
throw std::bad_alloc ();
}
//-----------------------------------------------------------------------------
void
null::deallocate (void *ptr, size_t bytes)
{
return deallocate (ptr, bytes, alignof (std::max_align_t));
}
//-----------------------------------------------------------------------------
// calling deallocate with a non-null pointer is undefined, but we may as well
// let the application continuing running if we're not in a debug context.
void
null::deallocate (void *ptr, size_t bytes, size_t align)
{
(void)ptr;
(void)bytes;
(void)align;
// cast to void* to assist some of the printing machinary in the assertion
CHECK_EQ (ptr, (void*)nullptr);
}
///////////////////////////////////////////////////////////////////////////////
std::byte*
null::begin (void)
{
return nullptr;
}
//-----------------------------------------------------------------------------
const std::byte*
null::begin (void) const
{
return nullptr;
}
//-----------------------------------------------------------------------------
std::byte*
null::end (void)
{ return nullptr; }
//-----------------------------------------------------------------------------
const std::byte*
null::end (void) const
{ return nullptr; }
//-----------------------------------------------------------------------------
size_t
null::offset (const void *ptr) const
{
return reinterpret_cast<uintptr_t> (ptr);
}
///////////////////////////////////////////////////////////////////////////////
void
null::reset (void)
{
;
}
///////////////////////////////////////////////////////////////////////////////
size_t
null::capacity (void) const
{
return 0;
}
//-----------------------------------------------------------------------------
size_t
null::used (void) const
{
return 0;
}
//-----------------------------------------------------------------------------
size_t
null::remain (void) const
{
return 0;
}