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
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_ServoComputedData_h
#define mozilla_ServoComputedData_h
class nsWindowSizes;
#include "mozilla/ServoStyleConsts.h"
/*
* ServoComputedData and its related types.
*/
namespace mozilla {
struct ServoWritingMode {
uint8_t mBits;
};
struct ServoComputedCustomProperties {
uintptr_t mInherited;
uintptr_t mNonInherited;
};
struct ServoRuleNode {
uintptr_t mPtr;
};
class ComputedStyle;
} // namespace mozilla
#define STYLE_STRUCT(name_) struct nsStyle##name_;
#include "nsStyleStructList.h"
#undef STYLE_STRUCT
class ServoComputedData;
struct ServoComputedDataForgotten {
// Make sure you manually mem::forget the backing ServoComputedData
// after calling this
explicit ServoComputedDataForgotten(const ServoComputedData* aValue)
: mPtr(aValue) {}
const ServoComputedData* mPtr;
};
/**
* We want C++ to be able to read the style struct fields of ComputedValues
* so we define this type on the C++ side and use the bindgenned version
* on the Rust side.
*/
class ServoComputedData {
friend class mozilla::ComputedStyle;
public:
// Constructs via memcpy. Will not move out of aValue.
explicit ServoComputedData(const ServoComputedDataForgotten aValue);
#define STYLE_STRUCT(name_) \
const nsStyle##name_* name_; \
const nsStyle##name_* Style##name_() const MOZ_NONNULL_RETURN { \
return name_; \
}
#include "nsStyleStructList.h"
#undef STYLE_STRUCT
void AddSizeOfExcludingThis(nsWindowSizes& aSizes) const;
mozilla::ServoWritingMode WritingMode() const { return writing_mode; }
private:
mozilla::ServoComputedCustomProperties custom_properties;
mozilla::ServoWritingMode writing_mode;
/// The effective zoom (as in, the CSS zoom property) of this style.
///
/// zoom is a non-inherited property, yet changes to it propagate through in
/// an inherited fashion, and all length resolution code need to access it.
/// This could, in theory, be stored in any other inherited struct, but it's
/// weird to have an inherited struct field depend on a non inherited
/// property.
///
/// So the style object itself is probably a reasonable place to store it.
mozilla::StyleZoom effective_zoom;
mozilla::StyleComputedValueFlags flags;
/// The rule node representing the ordered list of rules matched for this
/// node. Can be None for default values and text nodes. This is
/// essentially an optimization to avoid referencing the root rule node.
mozilla::ServoRuleNode rules;
/// The element's computed values if visited, only computed if there's a
/// relevant link for this element. A element's "relevant link" is the
/// element being matched if it is a link or the nearest ancestor link.
const mozilla::ComputedStyle* visited_style;
// C++ just sees this struct as a bucket of bits, and will
// do the wrong thing if we let it use the default copy ctor/assignment
// operator. Remove them so that there is no footgun.
//
// We remove the move ctor/assignment operator as well, because
// moves in C++ don't prevent destructors from being called,
// which will lead to double frees.
ServoComputedData& operator=(const ServoComputedData&) = delete;
ServoComputedData(const ServoComputedData&) = delete;
ServoComputedData&& operator=(const ServoComputedData&&) = delete;
ServoComputedData(const ServoComputedData&&) = delete;
};
#endif // mozilla_ServoComputedData_h
|