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/* -*- 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 */
#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"
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;
// 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"
void AddSizeOfExcludingThis(nsWindowSizes& aSizes) const;
mozilla::ServoWritingMode WritingMode() const { return writing_mode; }
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