1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
|
// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_DISPLAY_LOCK_DISPLAY_LOCK_CONTEXT_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_DISPLAY_LOCK_DISPLAY_LOCK_CONTEXT_H_
#include "third_party/blink/renderer/bindings/core/v8/active_script_wrappable.h"
#include "third_party/blink/renderer/bindings/core/v8/script_promise_resolver.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/platform/bindings/script_wrappable.h"
namespace blink {
class DisplayLockSuspendedHandle;
class Element;
class V8DisplayLockCallback;
class DisplayLockScopedLogger;
class CORE_EXPORT DisplayLockContext final
: public ScriptWrappable,
public ActiveScriptWrappable<DisplayLockContext>,
public ContextLifecycleObserver {
DEFINE_WRAPPERTYPEINFO();
USING_GARBAGE_COLLECTED_MIXIN(DisplayLockContext);
public:
// Conceptually the states are private, but made public for debugging /
// logging.
enum State {
kUninitialized,
kSuspended,
kCallbacksPending,
kDisconnected,
kCommitting,
kResolving,
kResolved
};
enum LifecycleUpdateState {
kNeedsStyle,
kNeedsLayout,
kNeedsPrePaint,
kNeedsPaint,
kDone
};
DisplayLockContext(Element*, ExecutionContext*);
~DisplayLockContext() override;
// GC functions.
void Trace(blink::Visitor*) override;
void Dispose();
// ContextLifecycleObserver overrides.
void ContextDestroyed(ExecutionContext*) override;
// ActiveScriptWrappable overrides. If there is an outstanding task scheduled
// to process the callback queue, then this return true.
// TODO(vmpstr): In the future this would also be true while we're doing
// co-operative work.
bool HasPendingActivity() const final;
// Notify that the lock was requested. Note that for a new context, this has
// to be called first. For an existing lock, this will either extend the
// lifetime of the current lock, or start acquiring a new lock (depending on
// whether this lock is active or passive).
void RequestLock(V8DisplayLockCallback*, ScriptState*);
// Returns true if the promise associated with this context was already
// resolved (or rejected).
bool IsResolved() const { return state_ == kResolved; }
// Returns a ScriptPromise associated with this context.
ScriptPromise Promise() const {
DCHECK(resolver_);
return resolver_->Promise();
}
// Called when the connected state may have changed.
void NotifyConnectedMayHaveChanged();
// Rejects the associated promise if one exists, and clears the current queue.
// This effectively makes the context finalized.
void RejectAndCleanUp();
// JavaScript interface implementation.
void schedule(V8DisplayLockCallback*);
DisplayLockSuspendedHandle* suspend();
Element* lockedElement() const;
// Lifecycle observation / state functions.
bool ShouldStyle() const;
void DidStyle();
bool ShouldLayout() const;
void DidLayout();
bool ShouldPrePaint() const;
void DidPrePaint();
bool ShouldPaint() const;
void DidPaint();
void DidAttachLayoutTree();
private:
friend class DisplayLockSuspendedHandle;
// Schedules a new callback. If this is the first callback to be scheduled,
// then a valid ScriptState must be provided, which will be used to create a
// new ScriptPromiseResolver. In other cases, the ScriptState is ignored.
void ScheduleCallback(V8DisplayLockCallback*);
// Processes the current queue of callbacks.
void ProcessQueue();
// Called by the suspended handle in order to resume context operations.
void Resume();
// Called by the suspended handle informing us that it was disposed without
// resuming, meaning it will never resume.
void NotifyWillNotResume();
// Schedule a task if one is required. Specifically, this would schedule a
// task if one was not already scheduled and if we need to either process
// callbacks or to resolve the associated promise.
void ScheduleTaskIfNeeded();
// A function that finishes resolving the promise by establishing a microtask
// checkpoint. Note that this should be scheduled after entering the
// kResolving state. If the state is still kResolving after the microtask
// checkpoint finishes (ie, the lock was not re-acquired), we enter the final
// kResolved state.
void FinishResolution();
// Initiate a commit.
void StartCommit();
// The following functions propagate dirty bits from the locked element up to
// the ancestors in order to be reached. They return true if the element or
// its subtree were dirty, and false otherwise.
bool MarkAncestorsForStyleRecalcIfNeeded();
bool MarkAncestorsForLayoutIfNeeded();
HeapVector<Member<V8DisplayLockCallback>> callbacks_;
Member<ScriptPromiseResolver> resolver_;
Member<Element> element_;
bool process_queue_task_scheduled_ = false;
unsigned suspended_count_ = 0;
State state_ = kUninitialized;
LifecycleUpdateState lifecycle_update_state_ = kNeedsStyle;
};
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_CORE_DISPLAY_LOCK_DISPLAY_LOCK_CONTEXT_H_
|
