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diff --git a/src/common/Utilities/TaskScheduler.h b/src/common/Utilities/TaskScheduler.h new file mode 100644 index 00000000000..f1fe7ea0a21 --- /dev/null +++ b/src/common/Utilities/TaskScheduler.h @@ -0,0 +1,650 @@ +/* + * 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 _TASK_SCHEDULER_H_ +#define _TASK_SCHEDULER_H_ + +#include <algorithm> +#include <chrono> +#include <vector> +#include <queue> +#include <memory> +#include <utility> +#include <set> + +#include <boost/optional.hpp> + +#include "Util.h" +#include "Duration.h" + +class TaskContext; + +/// The TaskScheduler class provides the ability to schedule std::function's in the near future. +/// Use TaskScheduler::Update to update the scheduler. +/// Popular methods are: +/// * Schedule (Schedules a std::function which will be executed in the near future). +/// * Schedules an asynchronous function which will be executed at the next update tick. +/// * Cancel, Delay & Reschedule (Methods to manipulate already scheduled tasks). +/// Tasks are organized in groups (uint), multiple tasks can have the same group id, +/// you can provide a group or not, but keep in mind that you can only manipulate specific tasks through its group id! +/// Tasks callbacks use the function signature void(TaskContext) where TaskContext provides +/// access to the function schedule plan which makes it possible to repeat the task +/// with the same duration or a new one. +/// It also provides access to the repeat counter which is useful for task that repeat itself often +/// but behave different every time (spoken event dialogs for example). +class TaskScheduler +{ + friend class TaskContext; + + // Time definitions (use steady clock) + typedef std::chrono::steady_clock clock_t; + typedef clock_t::time_point timepoint_t; + typedef clock_t::duration duration_t; + + // Task group type + typedef uint32 group_t; + // Task repeated type + typedef uint32 repeated_t; + // Task handle type + typedef std::function<void(TaskContext)> task_handler_t; + // Predicate type + typedef std::function<bool()> predicate_t; + // Success handle type + typedef std::function<void()> success_t; + + class Task + { + friend class TaskContext; + friend class TaskScheduler; + + timepoint_t _end; + duration_t _duration; + boost::optional<group_t> _group; + repeated_t _repeated; + task_handler_t _task; + + public: + // All Argument construct + Task(timepoint_t const& end, duration_t const& duration, boost::optional<group_t> const& group, + repeated_t const repeated, task_handler_t const& task) + : _end(end), _duration(duration), _group(group), _repeated(repeated), _task(task) { } + + // Minimal Argument construct + Task(timepoint_t const& end, duration_t const& duration, task_handler_t const& task) + : _end(end), _duration(duration), _group(boost::none), _repeated(0), _task(task) { } + + // Copy construct + Task(Task const&) = delete; + // Move construct + Task(Task&&) = delete; + // Copy Assign + Task& operator= (Task const&) = default; + // Move Assign + Task& operator= (Task&& right) = delete; + + // Order tasks by its end + inline bool operator< (Task const& other) const + { + return _end < other._end; + } + + inline bool operator> (Task const& other) const + { + return _end > other._end; + } + + // Compare tasks with its end + inline bool operator== (Task const& other) + { + return _end == other._end; + } + + // Returns true if the task is in the given group + inline bool IsInGroup(group_t const group) const + { + return _group == group; + } + }; + + typedef std::shared_ptr<Task> TaskContainer; + + /// Container which provides Task order, insert and reschedule operations. + struct Compare + { + bool operator() (TaskContainer const& left, TaskContainer const& right) + { + return (*left.get()) < (*right.get()); + }; + }; + + class TaskQueue + { + std::multiset<TaskContainer, Compare> container; + + public: + // Pushes the task in the container + void Push(TaskContainer&& task); + + /// Pops the task out of the container + TaskContainer Pop(); + + TaskContainer const& First() const; + + void Clear(); + + void RemoveIf(std::function<bool(TaskContainer const&)> const& filter); + + void ModifyIf(std::function<bool(TaskContainer const&)> const& filter); + + bool IsEmpty() const; + }; + + /// Contains a self reference to track if this object was deleted or not. + std::shared_ptr<TaskScheduler> self_reference; + + /// The current time point (now) + timepoint_t _now; + + /// The Task Queue which contains all task objects. + TaskQueue _task_holder; + + typedef std::queue<std::function<void()>> AsyncHolder; + + /// Contains all asynchronous tasks which will be invoked at + /// the next update tick. + AsyncHolder _asyncHolder; + + predicate_t _predicate; + + static bool EmptyValidator() + { + return true; + } + + static void EmptyCallback() + { + } + +public: + TaskScheduler() + : self_reference(this, [](TaskScheduler const*) { }), _now(clock_t::now()), _predicate(EmptyValidator) { } + + template<typename P> + TaskScheduler(P&& predicate) + : self_reference(this, [](TaskScheduler const*) { }), _now(clock_t::now()), _predicate(std::forward<P>(predicate)) { } + + TaskScheduler(TaskScheduler const&) = delete; + TaskScheduler(TaskScheduler&&) = delete; + TaskScheduler& operator= (TaskScheduler const&) = delete; + TaskScheduler& operator= (TaskScheduler&&) = delete; + + /// Sets a validator which is asked if tasks are allowed to be executed. + template<typename P> + TaskScheduler& SetValidator(P&& predicate) + { + _predicate = std::forward<P>(predicate); + return *this; + } + + /// Clears the validator which is asked if tasks are allowed to be executed. + TaskScheduler& ClearValidator(); + + /// Update the scheduler to the current time. + /// Calls the optional callback on successfully finish. + TaskScheduler& Update(success_t const& callback = EmptyCallback); + + /// Update the scheduler with a difftime in ms. + /// Calls the optional callback on successfully finish. + TaskScheduler& Update(size_t const milliseconds, success_t const& callback = EmptyCallback); + + /// Update the scheduler with a difftime. + /// Calls the optional callback on successfully finish. + template<class _Rep, class _Period> + TaskScheduler& Update(std::chrono::duration<_Rep, _Period> const& difftime, + success_t const& callback = EmptyCallback) + { + _now += difftime; + Dispatch(callback); + return *this; + } + + /// Schedule an callable function that is executed at the next update tick. + /// Its safe to modify the TaskScheduler from within the callable. + TaskScheduler& Async(std::function<void()> const& callable); + + /// Schedule an event with a fixed rate. + /// Never call this from within a task context! Use TaskContext::Schedule instead! + template<class _Rep, class _Period> + TaskScheduler& Schedule(std::chrono::duration<_Rep, _Period> const& time, + task_handler_t const& task) + { + return ScheduleAt(_now, time, task); + } + + /// Schedule an event with a fixed rate. + /// Never call this from within a task context! Use TaskContext::Schedule instead! + template<class _Rep, class _Period> + TaskScheduler& Schedule(std::chrono::duration<_Rep, _Period> const& time, + group_t const group, task_handler_t const& task) + { + return ScheduleAt(_now, time, group, task); + } + + /// Schedule an event with a randomized rate between min and max rate. + /// Never call this from within a task context! Use TaskContext::Schedule instead! + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskScheduler& Schedule(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max, task_handler_t const& task) + { + return Schedule(RandomDurationBetween(min, max), task); + } + + /// Schedule an event with a fixed rate. + /// Never call this from within a task context! Use TaskContext::Schedule instead! + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskScheduler& Schedule(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max, group_t const group, + task_handler_t const& task) + { + return Schedule(RandomDurationBetween(min, max), group, task); + } + + /// Cancels all tasks. + /// Never call this from within a task context! Use TaskContext::CancelAll instead! + TaskScheduler& CancelAll(); + + /// Cancel all tasks of a single group. + /// Never call this from within a task context! Use TaskContext::CancelGroup instead! + TaskScheduler& CancelGroup(group_t const group); + + /// Cancels all groups in the given std::vector. + /// Hint: Use std::initializer_list for this: "{1, 2, 3, 4}" + TaskScheduler& CancelGroupsOf(std::vector<group_t> const& groups); + + /// Delays all tasks with the given duration. + template<class _Rep, class _Period> + TaskScheduler& DelayAll(std::chrono::duration<_Rep, _Period> const& duration) + { + _task_holder.ModifyIf([&duration](TaskContainer const& task) -> bool + { + task->_end += duration; + return true; + }); + return *this; + } + + /// Delays all tasks with a random duration between min and max. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskScheduler& DelayAll(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return DelayAll(RandomDurationBetween(min, max)); + } + + /// Delays all tasks of a group with the given duration. + template<class _Rep, class _Period> + TaskScheduler& DelayGroup(group_t const group, std::chrono::duration<_Rep, _Period> const& duration) + { + _task_holder.ModifyIf([&duration, group](TaskContainer const& task) -> bool + { + if (task->IsInGroup(group)) + { + task->_end += duration; + return true; + } + else + return false; + }); + return *this; + } + + /// Delays all tasks of a group with a random duration between min and max. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskScheduler& DelayGroup(group_t const group, + std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return DelayGroup(group, RandomDurationBetween(min, max)); + } + + /// Reschedule all tasks with a given duration. + template<class _Rep, class _Period> + TaskScheduler& RescheduleAll(std::chrono::duration<_Rep, _Period> const& duration) + { + auto const end = _now + duration; + _task_holder.ModifyIf([end](TaskContainer const& task) -> bool + { + task->_end = end; + return true; + }); + return *this; + } + + /// Reschedule all tasks with a random duration between min and max. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskScheduler& RescheduleAll(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return RescheduleAll(RandomDurationBetween(min, max)); + } + + /// Reschedule all tasks of a group with the given duration. + template<class _Rep, class _Period> + TaskScheduler& RescheduleGroup(group_t const group, std::chrono::duration<_Rep, _Period> const& duration) + { + auto const end = _now + duration; + _task_holder.ModifyIf([end, group](TaskContainer const& task) -> bool + { + if (task->IsInGroup(group)) + { + task->_end = end; + return true; + } + else + return false; + }); + return *this; + } + + /// Reschedule all tasks of a group with a random duration between min and max. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskScheduler& RescheduleGroup(group_t const group, + std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return RescheduleGroup(group, RandomDurationBetween(min, max)); + } + +private: + /// Insert a new task to the enqueued tasks. + TaskScheduler& InsertTask(TaskContainer task); + + template<class _Rep, class _Period> + TaskScheduler& ScheduleAt(timepoint_t const& end, + std::chrono::duration<_Rep, _Period> const& time, task_handler_t const& task) + { + return InsertTask(TaskContainer(new Task(end + time, time, task))); + } + + /// Schedule an event with a fixed rate. + /// Never call this from within a task context! Use TaskContext::schedule instead! + template<class _Rep, class _Period> + TaskScheduler& ScheduleAt(timepoint_t const& end, + std::chrono::duration<_Rep, _Period> const& time, + group_t const group, task_handler_t const& task) + { + static repeated_t const DEFAULT_REPEATED = 0; + return InsertTask(TaskContainer(new Task(end + time, time, group, DEFAULT_REPEATED, task))); + } + + // Returns a random duration between min and max + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + static std::chrono::milliseconds + RandomDurationBetween(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + auto const milli_min = std::chrono::duration_cast<std::chrono::milliseconds>(min); + auto const milli_max = std::chrono::duration_cast<std::chrono::milliseconds>(max); + + // TC specific: use SFMT URandom + return std::chrono::milliseconds(urand(milli_min.count(), milli_max.count())); + } + + /// Dispatch remaining tasks + void Dispatch(success_t const& callback); +}; + +class TaskContext +{ + friend class TaskScheduler; + + /// Associated task + TaskScheduler::TaskContainer _task; + + /// Owner + std::weak_ptr<TaskScheduler> _owner; + + /// Marks the task as consumed + std::shared_ptr<bool> _consumed; + + /// Dispatches an action safe on the TaskScheduler + TaskContext& Dispatch(std::function<TaskScheduler&(TaskScheduler&)> const& apply); + +public: + // Empty constructor + TaskContext() + : _task(), _owner(), _consumed(std::make_shared<bool>(true)) { } + + // Construct from task and owner + explicit TaskContext(TaskScheduler::TaskContainer&& task, std::weak_ptr<TaskScheduler>&& owner) + : _task(task), _owner(owner), _consumed(std::make_shared<bool>(false)) { } + + // Copy construct + TaskContext(TaskContext const& right) + : _task(right._task), _owner(right._owner), _consumed(right._consumed) { } + + // Move construct + TaskContext(TaskContext&& right) + : _task(std::move(right._task)), _owner(std::move(right._owner)), _consumed(std::move(right._consumed)) { } + + // Copy assign + TaskContext& operator= (TaskContext const& right) + { + _task = right._task; + _owner = right._owner; + _consumed = right._consumed; + return *this; + } + + // Move assign + TaskContext& operator= (TaskContext&& right) + { + _task = std::move(right._task); + _owner = std::move(right._owner); + _consumed = std::move(right._consumed); + return *this; + } + + /// Returns true if the owner was deallocated and this context has expired. + bool IsExpired() const; + + /// Returns true if the event is in the given group + bool IsInGroup(TaskScheduler::group_t const group) const; + + /// Sets the event in the given group + TaskContext& SetGroup(TaskScheduler::group_t const group); + + /// Removes the group from the event + TaskContext& ClearGroup(); + + /// Returns the repeat counter which increases every time the task is repeated. + TaskScheduler::repeated_t GetRepeatCounter() const; + + /// Repeats the event and sets a new duration. + /// std::chrono::seconds(5) for example. + /// This will consume the task context, its not possible to repeat the task again + /// from the same task context! + template<class _Rep, class _Period> + TaskContext& Repeat(std::chrono::duration<_Rep, _Period> const& duration) + { + AssertOnConsumed(); + + // Set new duration, in-context timing and increment repeat counter + _task->_duration = duration; + _task->_end += duration; + _task->_repeated += 1; + (*_consumed) = true; + return Dispatch(std::bind(&TaskScheduler::InsertTask, std::placeholders::_1, _task)); + } + + /// Repeats the event with the same duration. + /// This will consume the task context, its not possible to repeat the task again + /// from the same task context! + TaskContext& Repeat() + { + return Repeat(_task->_duration); + } + + /// Repeats the event and set a new duration that is randomized between min and max. + /// std::chrono::seconds(5) for example. + /// This will consume the task context, its not possible to repeat the task again + /// from the same task context! + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& Repeat(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return Repeat(TaskScheduler::RandomDurationBetween(min, max)); + } + + /// Schedule a callable function that is executed at the next update tick from within the context. + /// Its safe to modify the TaskScheduler from within the callable. + TaskContext& Async(std::function<void()> const& callable); + + /// Schedule an event with a fixed rate from within the context. + /// Its possible that the new event is executed immediately! + /// Use TaskScheduler::Async to create a task + /// which will be called at the next update tick. + template<class _Rep, class _Period> + TaskContext& Schedule(std::chrono::duration<_Rep, _Period> const& time, + TaskScheduler::task_handler_t const& task) + { + auto const end = _task->_end; + return Dispatch([end, time, task](TaskScheduler& scheduler) -> TaskScheduler& + { + return scheduler.ScheduleAt<_Rep, _Period>(end, time, task); + }); + } + + /// Schedule an event with a fixed rate from within the context. + /// Its possible that the new event is executed immediately! + /// Use TaskScheduler::Async to create a task + /// which will be called at the next update tick. + template<class _Rep, class _Period> + TaskContext& Schedule(std::chrono::duration<_Rep, _Period> const& time, + TaskScheduler::group_t const group, TaskScheduler::task_handler_t const& task) + { + auto const end = _task->_end; + return Dispatch([end, time, group, task](TaskScheduler& scheduler) -> TaskScheduler& + { + return scheduler.ScheduleAt<_Rep, _Period>(end, time, group, task); + }); + } + + /// Schedule an event with a randomized rate between min and max rate from within the context. + /// Its possible that the new event is executed immediately! + /// Use TaskScheduler::Async to create a task + /// which will be called at the next update tick. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& Schedule(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max, TaskScheduler::task_handler_t const& task) + { + return Schedule(TaskScheduler::RandomDurationBetween(min, max), task); + } + + /// Schedule an event with a randomized rate between min and max rate from within the context. + /// Its possible that the new event is executed immediately! + /// Use TaskScheduler::Async to create a task + /// which will be called at the next update tick. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& Schedule(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max, TaskScheduler::group_t const group, + TaskScheduler::task_handler_t const& task) + { + return Schedule(TaskScheduler::RandomDurationBetween(min, max), group, task); + } + + /// Cancels all tasks from within the context. + TaskContext& CancelAll(); + + /// Cancel all tasks of a single group from within the context. + TaskContext& CancelGroup(TaskScheduler::group_t const group); + + /// Cancels all groups in the given std::vector from within the context. + /// Hint: Use std::initializer_list for this: "{1, 2, 3, 4}" + TaskContext& CancelGroupsOf(std::vector<TaskScheduler::group_t> const& groups); + + /// Delays all tasks with the given duration from within the context. + template<class _Rep, class _Period> + TaskContext& DelayAll(std::chrono::duration<_Rep, _Period> const& duration) + { + return Dispatch(std::bind(&TaskScheduler::DelayAll<_Rep, _Period>, std::placeholders::_1, duration)); + } + + /// Delays all tasks with a random duration between min and max from within the context. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& DelayAll(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return DelayAll(TaskScheduler::RandomDurationBetween(min, max)); + } + + /// Delays all tasks of a group with the given duration from within the context. + template<class _Rep, class _Period> + TaskContext& DelayGroup(TaskScheduler::group_t const group, std::chrono::duration<_Rep, _Period> const& duration) + { + return Dispatch(std::bind(&TaskScheduler::DelayGroup<_Rep, _Period>, std::placeholders::_1, group, duration)); + } + + /// Delays all tasks of a group with a random duration between min and max from within the context. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& DelayGroup(TaskScheduler::group_t const group, + std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return DelayGroup(group, TaskScheduler::RandomDurationBetween(min, max)); + } + + /// Reschedule all tasks with the given duration. + template<class _Rep, class _Period> + TaskContext& RescheduleAll(std::chrono::duration<_Rep, _Period> const& duration) + { + return Dispatch(std::bind(&TaskScheduler::RescheduleAll, std::placeholders::_1, duration)); + } + + /// Reschedule all tasks with a random duration between min and max. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& RescheduleAll(std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return RescheduleAll(TaskScheduler::RandomDurationBetween(min, max)); + } + + /// Reschedule all tasks of a group with the given duration. + template<class _Rep, class _Period> + TaskContext& RescheduleGroup(TaskScheduler::group_t const group, std::chrono::duration<_Rep, _Period> const& duration) + { + return Dispatch(std::bind(&TaskScheduler::RescheduleGroup<_Rep, _Period>, std::placeholders::_1, group, duration)); + } + + /// Reschedule all tasks of a group with a random duration between min and max. + template<class _RepLeft, class _PeriodLeft, class _RepRight, class _PeriodRight> + TaskContext& RescheduleGroup(TaskScheduler::group_t const group, + std::chrono::duration<_RepLeft, _PeriodLeft> const& min, + std::chrono::duration<_RepRight, _PeriodRight> const& max) + { + return RescheduleGroup(group, TaskScheduler::RandomDurationBetween(min, max)); + } + +private: + /// Asserts if the task was consumed already. + void AssertOnConsumed() const; + + /// Invokes the associated hook of the task. + void Invoke(); +}; + +#endif /// _TASK_SCHEDULER_H_ |