continuable/fluent++/CallbackContainer.h
2015-06-10 01:45:56 +02:00

117 lines
3.7 KiB
C++

/*
* Copyright (C) 2008-2015 TrinityCore <http://www.trinitycore.org/>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _CALLBACK_CONTAINER_H_
#define _CALLBACK_CONTAINER_H_
#include <unordered_map>
#include <boost/any.hpp>
#include <boost/optional.hpp>
#include "Callback.h"
class CallbackContainer
{
std::shared_ptr<CallbackContainer> self_reference;
typedef size_t handle_t;
size_t handle;
std::unordered_map<decltype(handle), boost::any> container;
template<typename _CTy, typename... Args>
struct ProxyFactory;
template<typename _CTy, typename... Args>
struct ProxyFactory<_CTy, std::tuple<Args...>>
{
// Creates a weak proxy callback which prevents invoking to an invalid context.
static callback_of_t<_CTy> CreateProxy(std::weak_ptr<CallbackContainer> const& weak_owner,
size_t const handle, weak_callback_of_t<_CTy> const& weak_callback)
{
return [=](Args&&... args)
{
// Try to get a pointer to the owner
if (auto const owner = weak_owner.lock())
// And to the wrapped functional itself
if (auto const callback = weak_callback.lock())
{
// Invoke the original callback
// FIXME: std::forward<Args..>(args...) causes errors when void
(*callback)(args...);
// Unregister the callback
owner->InvalidateCallback(handle);
}
};
}
};
public:
CallbackContainer()
: self_reference(this, [](decltype(this) me) { }), handle(0L) { }
~CallbackContainer() = default;
CallbackContainer(CallbackContainer const&) = delete;
CallbackContainer(CallbackContainer&&) = delete;
CallbackContainer& operator= (CallbackContainer const&) = delete;
CallbackContainer& operator= (CallbackContainer&&) = delete;
CallbackContainer& Clear()
{
container.clear();
return *this;
}
template<typename _CTy>
auto operator()(_CTy&& callback)
-> callback_of_t<_CTy>
{
// Create the shared callback
shared_callback_of_t<_CTy> shared_callback = make_shared_callback(std::forward<_CTy>(callback));
// Create a weak proxy callback which removes the callback on execute
auto const this_handle = handle++;
callback_of_t<_CTy> proxy =
ProxyFactory<_CTy, ::fu::argument_type_of_t<_CTy>>::
CreateProxy(self_reference, this_handle, shared_callback);
container.insert(std::make_pair(this_handle, boost::any(std::move(shared_callback))));
return std::move(proxy);
}
boost::optional<handle_t> GetLastCallbackHandle() const
{
if (handle == 0L)
return boost::none;
else
return boost::make_optional(handle);
}
CallbackContainer& InvalidateCallback(handle_t const handle)
{
container.erase(handle);
return *this;
}
};
#endif /// _CALLBACK_CONTAINER_H_