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Diffstat (limited to 'include/core/signal.h')
-rw-r--r-- | include/core/signal.h | 297 |
1 files changed, 0 insertions, 297 deletions
diff --git a/include/core/signal.h b/include/core/signal.h deleted file mode 100644 index be2984b..0000000 --- a/include/core/signal.h +++ /dev/null @@ -1,297 +0,0 @@ -/* - * Copyright © 2013 Canonical Ltd. - * - * This program is free software: you can redistribute it and/or modify it - * under the terms of the GNU Lesser General Public License version 3, - * as published by the Free Software Foundation. - * - * 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 Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - * - * Authored by: Thomas Voß <thomas.voss@canonical.com> - */ -#ifndef COM_UBUNTU_SIGNAL_H_ -#define COM_UBUNTU_SIGNAL_H_ - -#include <core/connection.h> - -#include <functional> -#include <iostream> -#include <list> -#include <mutex> -#include <set> - -namespace core -{ -/** - * @brief A signal class that observers can subscribe to. - * @tparam Arguments List of argument types passed on to observers when the signal is emitted. - */ -template<typename ...Arguments> -class Signal -{ -public: - /** - * @brief Slot is the function type that observers have to provide to connect to this signal. - */ - typedef std::function<void(Arguments...)> Slot; - -private: - struct SlotWrapper - { - void operator()(Arguments... args) - { - dispatcher(std::bind(slot, args...)); - } - - Slot slot; - Connection::Dispatcher dispatcher; - Connection connection; - }; - -public: - /** - * @brief Signal constructs a new instance. Never throws. - */ - inline Signal() noexcept(true) : d(new Private()) - { - } - - inline ~Signal() - { - std::lock_guard<std::mutex> lg(d->guard); - for (auto slot : d->slots) - slot.connection.reset(); - } - - // Copy construction, assignment and equality comparison are disabled. - Signal(const Signal&) = delete; - Signal& operator=(const Signal&) = delete; - bool operator==(const Signal&) const = delete; - - /** - * @brief Connects the provided slot to this signal instance. - * - * Calling this method is thread-safe and synchronized with any - * other connect, signal emission or disconnect calls. - * - * @param slot The function to be called when the signal is emitted. - * @return A connection object corresponding to the signal-slot connection. - */ - inline Connection connect(const Slot& slot) const - { - // Helpers to initialize an invalid connection. - static const Connection::Disconnector empty_disconnector{}; - static const Connection::DispatcherInstaller empty_dispatcher_installer{}; - - // The default dispatcher immediately executes the function object - // provided as argument on whatever thread is currently running. - static const Connection::Dispatcher default_dispatcher - = [](const std::function<void()>& handler) { handler(); }; - - Connection conn{empty_disconnector, empty_dispatcher_installer}; - - std::lock_guard<std::mutex> lg(d->guard); - - auto result = d->slots.insert( - d->slots.end(), - SlotWrapper{slot, default_dispatcher, conn}); - - // We implicitly share our internal state with the connection here - // by passing in our private bits contained in 'd' to the std::bind call. - // This admittedly uncommon approach allows us to cleanly manage connection - // and signal lifetimes without the need to mark everything as mutable. - conn.d->disconnector = std::bind( - &Private::disconnect_slot_for_iterator, - d, - result); - conn.d->dispatcher_installer = std::bind( - &Private::install_dispatcher_for_iterator, - d, - std::placeholders::_1, - result); - - return conn; - } - - /** - * @brief operator () emits the signal with the provided parameters. - * - * Please note that signal emissions might not be delivered immediately to - * registered slots, depending on whether the respective connection is dispatched - * via a queueing dispatcher. For that reason, the lifetime of the arguments has to - * exceed the scope of the call to this operator and its surrounding scope. - * - * @param args The arguments to be passed on to registered slots. - */ - inline void operator()(Arguments... args) - { - std::lock_guard<std::mutex> lg(d->guard); - for(auto slot : d->slots) - { - slot(args...); - } - } - -private: - struct Private - { - typedef std::list<SlotWrapper> SlotContainer; - - inline void disconnect_slot_for_iterator(typename SlotContainer::iterator it) - { - std::lock_guard<std::mutex> lg(guard); - slots.erase(it); - } - - inline void install_dispatcher_for_iterator(const Connection::Dispatcher& dispatcher, - typename SlotContainer::iterator it) - { - std::lock_guard<std::mutex> lg(guard); - it->dispatcher = dispatcher; - } - - std::mutex guard; - SlotContainer slots; - }; - std::shared_ptr<Private> d; -}; - -/** - * @brief A signal class that observers can subscribe to, - * template specialization for signals without arguments. - */ -template<> -class Signal<void> -{ -public: - /** - * @brief Slot is the function type that observers have to provide to connect to this signal. - */ - typedef std::function<void()> Slot; - -private: - struct SlotWrapper - { - void operator()() - { - dispatcher(slot); - } - - Slot slot; - Connection::Dispatcher dispatcher; - Connection connection; - }; - -public: - /** - * @brief Signal constructs a new instance. Never throws. - */ - inline Signal() noexcept(true) : d(new Private()) - { - } - - inline ~Signal() - { - std::lock_guard<std::mutex> lg(d->guard); - for (auto slot : d->slots) - slot.connection.reset(); - } - - // Copy construction, assignment and equality comparison are disabled. - Signal(const Signal&) = delete; - Signal& operator=(const Signal&) = delete; - bool operator==(const Signal&) const = delete; - - /** - * @brief Connects the provided slot to this signal instance. - * - * Calling this method is thread-safe and synchronized with any - * other connect, signal emission or disconnect calls. - * - * @param slot The function to be called when the signal is emitted. - * @return A connection object corresponding to the signal-slot connection. - */ - inline Connection connect(const Slot& slot) const - { - // Helpers to initialize an invalid connection. - static const Connection::Disconnector empty_disconnector{}; - static const Connection::DispatcherInstaller empty_dispatcher_installer{}; - - // The default dispatcher immediately executes the function object - // provided as argument on whatever thread is currently running. - static const Connection::Dispatcher default_dispatcher - = [](const std::function<void()>& handler) { handler(); }; - - Connection conn{empty_disconnector, empty_dispatcher_installer}; - - std::lock_guard<std::mutex> lg(d->guard); - - auto result = d->slots.insert( - d->slots.end(), - SlotWrapper{slot, default_dispatcher, conn}); - - // We implicitly share our internal state with the connection here - // by passing in our private bits contained in 'd' to the std::bind call. - // This admittedly uncommon approach allows us to cleanly manage connection - // and signal lifetimes without the need to mark everything as mutable. - conn.d->disconnector = std::bind( - &Private::disconnect_slot_for_iterator, - d, - result); - conn.d->dispatcher_installer = std::bind( - &Private::install_dispatcher_for_iterator, - d, - std::placeholders::_1, - result); - - return conn; - } - - /** - * @brief operator () emits the signal. - * - * Please note that signal emissions might not be delivered immediately to - * registered slots, depending on whether the respective connection is dispatched - * via a queueing dispatcher. - */ - inline void operator()() - { - std::lock_guard<std::mutex> lg(d->guard); - for(auto slot : d->slots) - { - slot(); - } - } - -private: - struct Private - { - typedef std::list<SlotWrapper> SlotContainer; - - inline void disconnect_slot_for_iterator(typename SlotContainer::iterator it) - { - std::lock_guard<std::mutex> lg(guard); - slots.erase(it); - } - - inline void install_dispatcher_for_iterator(const Connection::Dispatcher& dispatcher, - typename SlotContainer::iterator it) - { - std::lock_guard<std::mutex> lg(guard); - it->dispatcher = dispatcher; - } - - std::mutex guard; - SlotContainer slots; - }; - std::shared_ptr<Private> d; -}; -} - -#endif // COM_UBUNTU_SIGNAL_H_ |