153 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			153 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| 
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| #pragma once
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| 
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| #if !defined(MIJIN_ASYNC_SIGNAL_HPP_INCLUDED)
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| #define MIJIN_ASYNC_SIGNAL_HPP_INCLUDED 1
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| 
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| #include <algorithm>
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| #include <cstdint>
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| #include <functional>
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| #include <memory>
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| #include <mutex>
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| #include <vector>
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| #include "../util/flag.hpp"
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| 
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| namespace mijin
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| {
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| 
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| //
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| // public defines
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| //
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| 
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| //
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| // public constants
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| //
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| 
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| using signal_token_t = std::uint32_t;
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| inline constexpr signal_token_t INVALID_SIGNAL_TOKEN = std::numeric_limits<signal_token_t>::max();
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| 
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| //
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| // public types
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| //
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| 
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| MIJIN_DEFINE_FLAG(Oneshot);
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| 
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| template<typename... TArgs>
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| class Signal
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| {
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| public:
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|     using handler_t = std::function<void(TArgs...)>;
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|     using token_t = signal_token_t;
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| private:
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|     struct RegisteredHandler
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|     {
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|         handler_t callable;
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|         std::weak_ptr<void> referenced;
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|         token_t token;
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|         Oneshot oneshot = Oneshot::NO;
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|     };
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|     using handler_vector_t = std::vector<RegisteredHandler>;
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| private:
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|     handler_vector_t handlers_;
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|     token_t nextToken = 1;
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|     std::mutex handlersMutex_;
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| public:
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|     Signal() = default;
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|     Signal(const Signal&) = delete;
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|     Signal(Signal&&) noexcept = default;
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| public:
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|     Signal& operator=(const Signal&) = delete;
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|     Signal& operator=(Signal&&) noexcept = default;
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| public:
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|     template<typename THandler, typename TWeak = void>
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|     inline token_t connect(THandler handler, Oneshot oneshot = Oneshot::NO, std::weak_ptr<TWeak> referenced = std::weak_ptr<TWeak>()) noexcept;
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|     template<typename TObject, typename TWeak = void>
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|     inline token_t connect(TObject& object, void (TObject::* handler)(TArgs...), Oneshot oneshot = Oneshot::NO, std::weak_ptr<TWeak> referenced = std::weak_ptr<TWeak>()) noexcept;
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|     inline void disconnect(token_t token) noexcept;
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|     inline void emit(TArgs&&... args) noexcept;
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| };
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| 
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| //
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| // public functions
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| //
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| 
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| template<typename... TArgs>
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| template<typename THandler, typename TWeak>
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| inline auto Signal<TArgs...>::connect(THandler handler, Oneshot oneshot, std::weak_ptr<TWeak> referenced) noexcept -> token_t
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| {
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|     std::lock_guard lock(handlersMutex_);
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| 
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|     auto callable = handler_t(handler);
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|     handlers_.push_back({
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|         .callable = std::move(callable),
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|         .referenced = std::move(referenced),
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|         .token = nextToken,
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|         .oneshot = oneshot
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|     });
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| 
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|     return nextToken++;
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| }
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| 
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| template<typename... TArgs>
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| template<typename TObject, typename TWeak>
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| inline auto Signal<TArgs...>::connect(TObject& object, void (TObject::* handler)(TArgs...), Oneshot oneshot, std::weak_ptr<TWeak> referenced) noexcept -> token_t
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| {
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|     std::lock_guard lock(handlersMutex_);
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| 
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|     auto callable = [object = &object, handler](TArgs... args)
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|     {
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|         std::invoke(handler, object, std::forward<TArgs>(args)...);
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|     };
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|     handlers_.push_back({
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|         .callable = std::move(callable),
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|         .referenced = std::move(referenced),
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|         .token = nextToken,
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|         .oneshot = oneshot
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|     });
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| 
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|     return nextToken++;
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| }
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| 
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| template<typename... TArgs>
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| inline void Signal<TArgs...>::disconnect(token_t token) noexcept
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| {
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|     std::lock_guard lock(handlersMutex_);
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| 
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|     auto it = std::remove_if(handlers_.begin(), handlers_.end(), [token](const RegisteredHandler& handler)
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|     {
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|         return handler.token == token;
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|     });
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|     handlers_.erase(it, handlers_.end());
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| }
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| 
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| template<typename... TArgs>
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| inline void Signal<TArgs...>::emit(TArgs&&... args) noexcept
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| {
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|     std::lock_guard lock(handlersMutex_);
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|     
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|     // first erase any handlers with expired references
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|     // auto it = std::remove_if(handlers_.begin(), handlers_.end(), [](const RegisteredHandler& handler)
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|     // {
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|     //     return handler.referenced.expired();
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|     // });
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|     // handlers_.erase(it, handlers_.end());
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|     // TODO: this doesn't really work since expired() also returns true if the pointer was never set
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| 
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|     // invoke all handlers
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|     for (RegisteredHandler& handler : handlers_)
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|     {
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|         handler.callable(std::forward<TArgs>(args)...);
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|     }
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| 
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|     // remove any oneshot
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|     auto it = std::remove_if(handlers_.begin(), handlers_.end(), [](const RegisteredHandler& handler)
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|     {
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|         return handler.oneshot;
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|     });
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|     handlers_.erase(it, handlers_.end());
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| }
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| 
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| } // namespace mijin
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| 
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| #endif // !defined(MIJIN_ASYNC_SIGNAL_HPP_INCLUDED)
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