mirror of
https://github.com/matrix-construct/construct
synced 2024-08-22 01:24:53 +02:00
87 lines
2.5 KiB
C++
87 lines
2.5 KiB
C++
// Copyright (C) Matrix Construct Developers, Authors & Contributors
|
|
// Copyright (C) 2016-2018 Jason Volk
|
|
//
|
|
// Permission to use, copy, modify, and/or distribute this software for any
|
|
// purpose with or without fee is hereby granted, provided that the above
|
|
// copyright notice and this permission notice is present in all copies.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
// DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
|
|
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
|
|
// IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
// POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_UTIL_UNIQUE_ITERATOR_H
|
|
|
|
namespace ircd::util
|
|
{
|
|
template<class container,
|
|
class iterator = typename container::iterator>
|
|
struct unique_iterator;
|
|
|
|
template<class container>
|
|
struct unique_const_iterator;
|
|
}
|
|
|
|
//
|
|
// For objects using the pattern of adding their own instance to a container
|
|
// in their constructor, storing an iterator as a member, and then removing
|
|
// themselves using the iterator in their destructor. It is unsafe to do that.
|
|
// Use this instead; or better, use ircd::instance_list<>
|
|
//
|
|
template<class container,
|
|
class iterator>
|
|
struct ircd::util::unique_iterator
|
|
{
|
|
container *c;
|
|
iterator it;
|
|
|
|
unique_iterator(container &c, iterator it)
|
|
:c{&c}
|
|
,it{std::move(it)}
|
|
{}
|
|
|
|
unique_iterator()
|
|
:c{nullptr}
|
|
{}
|
|
|
|
unique_iterator(const unique_iterator &) = delete;
|
|
unique_iterator(unique_iterator &&o) noexcept
|
|
:c{std::move(o.c)}
|
|
,it{std::move(o.it)}
|
|
{
|
|
o.c = nullptr;
|
|
}
|
|
|
|
unique_iterator &operator=(const unique_iterator &) = delete;
|
|
unique_iterator &operator=(unique_iterator &&o) noexcept
|
|
{
|
|
this->~unique_iterator();
|
|
c = std::move(o.c);
|
|
it = std::move(o.it);
|
|
o.c = nullptr;
|
|
return *this;
|
|
}
|
|
|
|
~unique_iterator() noexcept
|
|
{
|
|
if(c)
|
|
c->erase(it);
|
|
}
|
|
};
|
|
|
|
template<class container>
|
|
struct ircd::util::unique_const_iterator
|
|
:unique_iterator<container, typename container::const_iterator>
|
|
{
|
|
using iterator_type = typename container::const_iterator;
|
|
using unique_iterator<container, iterator_type>::unique_iterator;
|
|
};
|