1 | // Copyright 2020 The Marl Authors. |
2 | // |
3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
4 | // you may not use this file except in compliance with the License. |
5 | // You may obtain a copy of the License at |
6 | // |
7 | // https://www.apache.org/licenses/LICENSE-2.0 |
8 | // |
9 | // Unless required by applicable law or agreed to in writing, software |
10 | // distributed under the License is distributed on an "AS IS" BASIS, |
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
12 | // See the License for the specific language governing permissions and |
13 | // limitations under the License. |
14 | |
15 | #ifndef marl_task_h |
16 | #define marl_task_h |
17 | |
18 | #include "export.h" |
19 | |
20 | #include <functional> |
21 | |
22 | namespace marl { |
23 | |
24 | // Task is a unit of work for the scheduler. |
25 | class Task { |
26 | public: |
27 | using Function = std::function<void()>; |
28 | |
29 | enum class Flags { |
30 | None = 0, |
31 | |
32 | // SameThread ensures the task will be run on the same thread that scheduled |
33 | // the task. This can offer performance improvements if the current thread |
34 | // is immediately going to block on the newly scheduled task, by reducing |
35 | // overheads of waking another thread. |
36 | SameThread = 1, |
37 | }; |
38 | |
39 | MARL_NO_EXPORT inline Task(); |
40 | MARL_NO_EXPORT inline Task(const Task&); |
41 | MARL_NO_EXPORT inline Task(Task&&); |
42 | MARL_NO_EXPORT inline Task(const Function& function, |
43 | Flags flags = Flags::None); |
44 | MARL_NO_EXPORT inline Task(Function&& function, Flags flags = Flags::None); |
45 | MARL_NO_EXPORT inline Task& operator=(const Task&); |
46 | MARL_NO_EXPORT inline Task& operator=(Task&&); |
47 | MARL_NO_EXPORT inline Task& operator=(const Function&); |
48 | MARL_NO_EXPORT inline Task& operator=(Function&&); |
49 | |
50 | // operator bool() returns true if the Task has a valid function. |
51 | MARL_NO_EXPORT inline operator bool() const; |
52 | |
53 | // operator()() runs the task. |
54 | MARL_NO_EXPORT inline void operator()() const; |
55 | |
56 | // is() returns true if the Task was created with the given flag. |
57 | MARL_NO_EXPORT inline bool is(Flags flag) const; |
58 | |
59 | private: |
60 | Function function; |
61 | Flags flags = Flags::None; |
62 | }; |
63 | |
64 | Task::Task() {} |
65 | Task::Task(const Task& o) : function(o.function), flags(o.flags) {} |
66 | Task::Task(Task&& o) : function(std::move(o.function)), flags(o.flags) {} |
67 | Task::Task(const Function& function, Flags flags /* = Flags::None */) |
68 | : function(function), flags(flags) {} |
69 | Task::Task(Function&& function, Flags flags /* = Flags::None */) |
70 | : function(std::move(function)), flags(flags) {} |
71 | Task& Task::operator=(const Task& o) { |
72 | function = o.function; |
73 | flags = o.flags; |
74 | return *this; |
75 | } |
76 | Task& Task::operator=(Task&& o) { |
77 | function = std::move(o.function); |
78 | flags = o.flags; |
79 | return *this; |
80 | } |
81 | |
82 | Task& Task::operator=(const Function& f) { |
83 | function = f; |
84 | flags = Flags::None; |
85 | return *this; |
86 | } |
87 | Task& Task::operator=(Function&& f) { |
88 | function = std::move(f); |
89 | flags = Flags::None; |
90 | return *this; |
91 | } |
92 | Task::operator bool() const { |
93 | return function.operator bool(); |
94 | } |
95 | |
96 | void Task::operator()() const { |
97 | function(); |
98 | } |
99 | |
100 | bool Task::is(Flags flag) const { |
101 | return (static_cast<int>(flags) & static_cast<int>(flag)) == |
102 | static_cast<int>(flag); |
103 | } |
104 | |
105 | } // namespace marl |
106 | |
107 | #endif // marl_task_h |
108 | |