协程sleep的重新思考和整理

README.md

@@ -12,7 +12,7 @@ librf是一个基于C++ Coroutines提案 ‘Stackless Resumable Functions’编
 librf有以下特点：
 
  *   1.基于C++17提案'Stackless Resumable Functions'编写的非对称stackless协程库，可以以同步的方式编写简单的代码，同时获得异步的性能
- *   2.理论上支持海量协程, 创建100万个协程只需使用<820M>物理内存
+ *   2.理论上支持海量协程, 创建100万个协程只需使用<430M>物理内存
  *   3.提供协程锁(mutex), 定时器, channel等特性, 帮助用户更加容易地编写程序 
  *   4.可以很好的跟asio,libuv等库结合，能跟现有的callback范式的异步/延迟代码很好的结合
  *   5.目前还处于实验状态，不对今后正式的C++ Coroutines支持有任何正式的承诺

librf/src/def.h

@@ -71,6 +71,7 @@ namespace resumef
 		already_acquired,	// attempt to get another future
 		unlock_more,		// unlock 次数多余lock次数
 		read_before_write,	// 0容量的channel，先读后写
+		timer_canceled,		// 定时器被意外取消
 
 		max__
 	};
@@ -108,6 +109,16 @@ namespace resumef
 		}
 	};
 
+	struct timer_canceled_exception : public std::exception
+	{
+		error_code _error;
+		timer_canceled_exception(error_code fe)
+			: exception(get_error_string(fe, "timer canceled"))
+			, _error(fe)
+		{
+		}
+	};
+
 	struct scheduler;
 	struct state_base;
 

librf/src/scheduler.cpp

@@ -18,6 +18,7 @@ namespace resumef
 		"already_acquired",
 		"unlock_more",
 		"read_before_write",
+		"timer_canceled",
 	};
 
 	static char sz_future_error_buffer[256];

librf/src/sleep.cpp

@@ -4,15 +4,17 @@
 
 namespace resumef
 {
-
-	future_t<bool> sleep_until_(const std::chrono::system_clock::time_point& tp_, scheduler & scheduler_)
+	future_vt sleep_until_(const std::chrono::system_clock::time_point& tp_, scheduler & scheduler_)
 	{
-		promise_t<bool> awaitable;
+		promise_vt awaitable;
 
 		scheduler_.timer()->add(tp_, 
 			[st = awaitable._state](bool cancellation_requested)
 			{
-				st->set_value(cancellation_requested);
+				if (cancellation_requested)
+					st->throw_exception(timer_canceled_exception{ error_code::timer_canceled });
+				else
+					st->set_value();
 			});
 
 		return awaitable.get_future();

librf/src/sleep.h

@@ -1,34 +1,38 @@
+//协程的定时器
+//如果定时器被取消了，则会抛 timer_canceled_exception 异常
+//不使用co_await而单独sleep_for/sleep_until，是错误的用法，并不能达到等待的目的。而仅仅是添加了一个无效的定时器，造成无必要的内存使用
+//
 #pragma once
 
 namespace resumef
 {
 	struct scheduler;
 
-	RF_API future_t<bool> sleep_until_(const std::chrono::system_clock::time_point& tp_, scheduler & scheduler_);
+	RF_API future_vt sleep_until_(const std::chrono::system_clock::time_point& tp_, scheduler & scheduler_);
 
-	inline future_t<bool> sleep_for_(const std::chrono::system_clock::duration& dt_, scheduler & scheduler_)
+	inline future_vt sleep_for_(const std::chrono::system_clock::duration& dt_, scheduler & scheduler_)
 	{
 		return std::move(sleep_until_(std::chrono::system_clock::now() + dt_, scheduler_));
 	}
 
 	template<class _Rep, class _Period>
-	future_t<bool> sleep_for(const std::chrono::duration<_Rep, _Period>& dt_, scheduler & scheduler_)
+	future_vt sleep_for(const std::chrono::duration<_Rep, _Period>& dt_, scheduler & scheduler_)
 	{
 		return std::move(sleep_for_(std::chrono::duration_cast<std::chrono::system_clock::duration>(dt_), scheduler_));
 	}
 	template<class _Rep, class _Period>
-	future_t<bool> sleep_for(const std::chrono::duration<_Rep, _Period>& dt_)
+	future_vt sleep_for(const std::chrono::duration<_Rep, _Period>& dt_)
 	{
 		return std::move(sleep_for_(std::chrono::duration_cast<std::chrono::system_clock::duration>(dt_), *this_scheduler()));
 	}
 
 	template<class _Clock, class _Duration = typename _Clock::duration>
-	future_t<bool> sleep_until(const std::chrono::time_point<_Clock, _Duration>& tp_, scheduler & scheduler_)
+	future_vt sleep_until(const std::chrono::time_point<_Clock, _Duration>& tp_, scheduler & scheduler_)
 	{
 		return std::move(sleep_until_(std::chrono::time_point_cast<std::chrono::system_clock::duration>(tp_), scheduler_));
 	}
 	template<class _Clock, class _Duration>
-	future_t<bool> sleep_until(const std::chrono::time_point<_Clock, _Duration>& tp_)
+	future_vt sleep_until(const std::chrono::time_point<_Clock, _Duration>& tp_)
 	{
 		return std::move(sleep_until_(std::chrono::time_point_cast<std::chrono::system_clock::duration>(tp_), *this_scheduler()));
 	}

librf/src/state.cpp

@@ -47,39 +47,39 @@ namespace resumef
 #endif
 	}
 
-	void state_base::set_value_none_lock()
-	{
-		// Set all members first as calling coroutine may reset stuff here.
-		_ready = true;
-
-		if (_coro)
-		{
+	void state_base::set_value_none_lock()
+	{
+		// Set all members first as calling coroutine may reset stuff here.
+		_ready = true;
+
+		if (_coro)
+		{
 #if RESUMEF_ENABLE_MULT_SCHEDULER
-			auto sch_ = this->current_scheduler();
-#else
-			auto sch_ = this_scheduler();
-#endif
-			if(sch_) sch_->push_task_internal(new awaitable_task_t<state_base>(this));
-		}
-	}
+			auto sch_ = this->current_scheduler();
+#else
+			auto sch_ = this_scheduler();
+#endif
+			if(sch_) sch_->push_task_internal(new awaitable_task_t<state_base>(this));
+		}
+	}
 
 	void state_base::set_exception(std::exception_ptr && e_)
 	{
 		scoped_lock<lock_type> __guard(_mtx);
 
 		_exception = std::move(e_);
-		// Set all members first as calling coroutine may reset stuff here.
-		_ready = true;
-
-		if (_coro)
-		{
+		// Set all members first as calling coroutine may reset stuff here.
+		_ready = true;
+
+		if (_coro)
+		{
 #if RESUMEF_ENABLE_MULT_SCHEDULER
-			auto sch_ = this->current_scheduler();
+			auto sch_ = this->current_scheduler();
 #else
-			auto sch_ = this_scheduler();
+			auto sch_ = this_scheduler();
 #endif
-			if (sch_) sch_->push_task_internal(new awaitable_task_t<state_base>(this));
-		}
+			if (sch_) sch_->push_task_internal(new awaitable_task_t<state_base>(this));
+		}
 	}
 
 	void state_base::await_suspend(coroutine_handle<> resume_cb)

librf/src/state.h

@@ -35,7 +35,7 @@ namespace resumef
 		std::atomic<bool> _done = false;
 
 	public:
-		state_base()
+		state_base() noexcept
 		{
 #if RESUMEF_DEBUG_COUNTER
 			++g_resumef_state_count;
@@ -190,7 +190,16 @@ namespace resumef
 			_value = std::forward<value_type>(t);
 			state_base::set_value_none_lock();
 		}
-		_Ty & get_value()
+
+		value_type & set_value__()
+		{
+			scoped_lock<lock_type> __guard(_mtx);
+			state_base::set_value_none_lock();
+
+			return _value;
+		}
+		
+		value_type & get_value()
 		{
 			scoped_lock<lock_type> __guard(_mtx);
 
@@ -198,6 +207,7 @@ namespace resumef
 				throw future_exception{ error_code::not_ready };
 			return _value;
 		}
+
 		void reset()
 		{
 			scoped_lock<lock_type> __guard(_mtx);

tutorial/test_async_sleep.cpp

@@ -13,13 +13,20 @@ future_vt test_sleep_use_timer()
 {
 	using namespace std::chrono;
 
+	resumef::sleep_for(100ms);		//incorrect!!!
+
 	co_await resumef::sleep_for(100ms);
 	std::cout << "timer after 100ms." << std::endl;
 
-	if (co_await resumef::sleep_until(system_clock::now() + 200ms))
-		std::cout << "timer canceled." << std::endl;
-	else
+	try
+	{
+		co_await resumef::sleep_until(system_clock::now() + 200ms);
 		std::cout << "timer after 200ms." << std::endl;
+	}
+	catch (resumef::timer_canceled_exception)
+	{
+		std::cout << "timer canceled." << std::endl;
+	}
 }
 
 void test_wait_all_events_with_signal_by_sleep()
@@ -37,7 +44,7 @@ void test_wait_all_events_with_signal_by_sleep()
 	};
 
 	srand((int)time(nullptr));
-	for(size_t i=0; i<_countof(evts); ++i)
+	for (size_t i = 0; i < _countof(evts); ++i)
 	{
 		go[&, i]() -> future_vt
 		{

vs_proj/librf.cpp

@@ -22,7 +22,9 @@ extern void resumable_main_benchmark_mem();
 
 int main(int argc, const char * argv[])
 {
+	resumable_main_sleep();
 	//resumable_main_resumable();
+/*
 	resumable_main_when_all();
 	resumable_main_multi_thread();
 	resumable_main_yield_return();
@@ -38,6 +40,7 @@ int main(int argc, const char * argv[])
 	resumable_main_channel();
 	resumable_main_cb();
 	resumable_main_exception();
+*/
 
 	return 0;
 }