1 | /* |
2 | * Copyright (C) 2014 Yoav Weiss (yoav@yoav.ws) |
3 | * Copyright (C) 2015 Akamai Technologies Inc. All rights reserved. |
4 | * |
5 | * This library is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU Library General Public |
7 | * License as published by the Free Software Foundation; either |
8 | * version 2 of the License, or (at your option) any later version. |
9 | * |
10 | * This library is distributed in the hope that it will be useful, |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | * Library General Public License for more details. |
14 | * |
15 | * You should have received a copy of the GNU Library General Public License |
16 | * along with this library; see the file COPYING.LIB. If not, write to |
17 | * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
18 | * Boston, MA 02110-1301, USA. |
19 | * |
20 | */ |
21 | |
22 | #pragma once |
23 | |
24 | #include "Timer.h" |
25 | #include <wtf/Forward.h> |
26 | #include <wtf/Vector.h> |
27 | |
28 | namespace WebCore { |
29 | |
30 | class MicrotaskQueue; |
31 | class ScriptExecutionContext; |
32 | |
33 | class Microtask { |
34 | public: |
35 | virtual ~Microtask() |
36 | { |
37 | } |
38 | |
39 | enum class Result { |
40 | Done, |
41 | KeepInQueue |
42 | }; |
43 | |
44 | virtual Result run() = 0; |
45 | |
46 | protected: |
47 | void removeSelfFromQueue(MicrotaskQueue&); |
48 | }; |
49 | |
50 | class VoidMicrotask final : public Microtask { |
51 | WTF_MAKE_FAST_ALLOCATED; |
52 | public: |
53 | explicit VoidMicrotask(Function<void()>&& function) |
54 | : m_function(WTFMove(function)) |
55 | { |
56 | } |
57 | |
58 | private: |
59 | Result run() final |
60 | { |
61 | m_function(); |
62 | return Result::Done; |
63 | } |
64 | |
65 | Function<void()> m_function; |
66 | }; |
67 | |
68 | class MicrotaskQueue { |
69 | friend NeverDestroyed<MicrotaskQueue>; |
70 | friend class Microtask; |
71 | public: |
72 | WEBCORE_EXPORT static MicrotaskQueue& mainThreadQueue(); |
73 | WEBCORE_EXPORT static MicrotaskQueue& contextQueue(ScriptExecutionContext&); |
74 | |
75 | WEBCORE_EXPORT MicrotaskQueue(); |
76 | WEBCORE_EXPORT ~MicrotaskQueue(); |
77 | |
78 | WEBCORE_EXPORT void append(std::unique_ptr<Microtask>&&); |
79 | WEBCORE_EXPORT void performMicrotaskCheckpoint(); |
80 | |
81 | private: |
82 | WEBCORE_EXPORT void remove(const Microtask&); |
83 | |
84 | void timerFired(); |
85 | |
86 | bool m_performingMicrotaskCheckpoint = false; |
87 | Vector<std::unique_ptr<Microtask>> m_microtaskQueue; |
88 | |
89 | // FIXME: Instead of a Timer, we should have a centralized Event Loop that calls performMicrotaskCheckpoint() |
90 | // on every iteration, implementing https://html.spec.whatwg.org/multipage/webappapis.html#processing-model-9 |
91 | Timer m_timer; |
92 | }; |
93 | |
94 | } // namespace WebCore |
95 | |