2 * Copyright (c) 2011 Sveriges Television AB <info@casparcg.com>
4 * This file is part of CasparCG (www.casparcg.com).
6 * CasparCG is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * CasparCG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with CasparCG. If not, see <http://www.gnu.org/licenses/>.
19 * Author: Robert Nagy, ronag89@gmail.com
25 #include "enum_class.h"
27 #include "blocking_bounded_queue_adapter.h"
28 #include "blocking_priority_queue.h"
31 #include <tbb/atomic.h>
32 #include <tbb/concurrent_priority_queue.h>
34 #include <boost/thread.hpp>
35 #include <boost/optional.hpp>
36 #include <boost/assign/list_of.hpp>
42 struct task_priority_def
54 typedef enum_class<task_priority_def> task_priority;
56 class executor /* final */
58 executor(const executor&);
59 executor& operator=(const executor&);
61 typedef blocking_priority_queue<std::function<void()>, task_priority> function_queue_t;
63 const std::wstring name_;
64 tbb::atomic<bool> is_running_;
65 boost::thread thread_;
66 function_queue_t execution_queue_;
69 executor(const std::wstring& name)
71 , execution_queue_(512, boost::assign::list_of
72 (task_priority::lowest_priority)
73 (task_priority::lower_priority)
74 (task_priority::low_priority)
75 (task_priority::normal_priority)
76 (task_priority::high_priority)
77 (task_priority::higher_priority))
80 thread_ = boost::thread([this]{run();});
87 internal_begin_invoke([=]
94 CASPAR_LOG_CURRENT_EXCEPTION();
100 template<typename Func>
101 auto begin_invoke(Func&& func, task_priority priority = task_priority::normal_priority) -> boost::unique_future<decltype(func())> // noexcept
104 CASPAR_THROW_EXCEPTION(invalid_operation() << msg_info("executor not running.") << source_info(name_));
106 return internal_begin_invoke(std::forward<Func>(func), priority);
109 template<typename Func>
110 auto invoke(Func&& func, task_priority prioriy = task_priority::normal_priority) -> decltype(func()) // noexcept
112 if(is_current()) // Avoids potential deadlock.
115 return begin_invoke(std::forward<Func>(func), prioriy).get();
118 void yield(task_priority minimum_priority)
121 CASPAR_THROW_EXCEPTION(invalid_operation() << msg_info("Executor can only yield inside of thread context.") << source_info(name_));
123 std::function<void ()> func;
125 while (execution_queue_.try_pop(func, minimum_priority))
129 void set_capacity(function_queue_t::size_type capacity)
131 execution_queue_.set_capacity(capacity);
134 function_queue_t::size_type capacity() const
136 return execution_queue_.capacity();
141 return execution_queue_.space_available() == 0;
146 std::function<void ()> func;
147 while(execution_queue_.try_pop(func));
160 invoke([]{}, task_priority::lowest_priority);
163 function_queue_t::size_type size() const
165 return execution_queue_.size();
168 bool is_running() const
173 bool is_current() const
175 return boost::this_thread::get_id() == thread_.get_id();
180 std::wstring print() const
182 return L"executor[" + name_ + L"]";
185 template<typename Func>
186 auto internal_begin_invoke(
188 task_priority priority = task_priority::normal_priority) -> boost::unique_future<decltype(func())> // noexcept
190 typedef typename std::remove_reference<Func>::type function_type;
191 typedef decltype(func()) result_type;
192 typedef boost::packaged_task<result_type> task_type;
194 std::unique_ptr<task_type> task;
196 // Use pointers since the boost thread library doesn't fully support move semantics.
198 auto raw_func2 = new function_type(std::forward<Func>(func));
201 task.reset(new task_type([raw_func2]() -> result_type
203 std::unique_ptr<function_type> func2(raw_func2);
213 task->set_wait_callback(std::function<void(task_type&)>([=](task_type& my_task) // The std::function wrapper is required in order to add ::result_type to functor class.
217 if(is_current()) // Avoids potential deadlock.
220 catch(boost::task_already_started&){}
223 auto future = task->get_future();
225 auto raw_task = task.release();
226 auto function = [raw_task]
228 std::unique_ptr<task_type> task(raw_task);
233 catch(boost::task_already_started&){}
236 if (!execution_queue_.try_push(priority, function))
238 CASPAR_LOG(debug) << print() << L" Overflow. Blocking caller.";
239 execution_queue_.push(priority, function);
242 return std::move(future);
245 void run() // noexcept
247 win32_exception::install_handler();
252 std::function<void ()> func;
253 execution_queue_.pop(func);
258 CASPAR_LOG_CURRENT_EXCEPTION();