1/*
2 * Copyright (c) 2020 - 2023 the ThorVG project. All rights reserved.
3
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10
11 * The above copyright notice and this permission notice shall be included in all
12 * copies or substantial portions of the Software.
13
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20 * SOFTWARE.
21 */
22
23#ifndef _TVG_TASK_SCHEDULER_H_
24#define _TVG_TASK_SCHEDULER_H_
25
26#include <mutex>
27#include <condition_variable>
28#include "tvgCommon.h"
29
30namespace tvg
31{
32
33struct Task;
34
35struct TaskScheduler
36{
37 static unsigned threads();
38 static void init(unsigned threads);
39 static void term();
40 static void request(Task* task);
41};
42
43struct Task
44{
45private:
46 mutex mtx;
47 condition_variable cv;
48 bool ready = true;
49 bool pending = false;
50
51public:
52 virtual ~Task() = default;
53
54 void done()
55 {
56 if (!pending) return;
57
58 unique_lock<mutex> lock(mtx);
59 while (!ready) cv.wait(lock);
60 pending = false;
61 }
62
63protected:
64 virtual void run(unsigned tid) = 0;
65
66private:
67 void operator()(unsigned tid)
68 {
69 run(tid);
70
71 lock_guard<mutex> lock(mtx);
72 ready = true;
73 cv.notify_one();
74 }
75
76 void prepare()
77 {
78 ready = false;
79 pending = true;
80 }
81
82 friend struct TaskSchedulerImpl;
83};
84
85}
86
87#endif //_TVG_TASK_SCHEDULER_H_
88
89