layout: Stop doing unsafe transmutes between refcell references.

This commit splits the style and layout data in two separate refcells.

These transmutes have been a source of trouble (for example on Android), and
they feel like a hack anyway.

Fixes #16982
This commit is contained in:
Emilio Cobos Álvarez 2017-05-24 19:15:12 +02:00
parent bb310efbb9
commit deaa935f5b
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GPG key ID: 056B727BB9C1027C
9 changed files with 79 additions and 94 deletions

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@ -2,16 +2,32 @@
* 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/. */
use atomic_refcell::AtomicRefCell;
use construct::ConstructionResult;
use script_layout_interface::PartialPersistentLayoutData;
use script_layout_interface::StyleData;
#[repr(C)]
pub struct StyleAndLayoutData {
/// Data accessed by script_layout_interface. This must be first to allow
/// casting between StyleAndLayoutData and StyleData.
pub style_data: StyleData,
/// The layout data associated with a node.
pub layout_data: AtomicRefCell<LayoutData>,
}
impl StyleAndLayoutData {
pub fn new() -> Self {
Self {
style_data: StyleData::new(),
layout_data: AtomicRefCell::new(LayoutData::new()),
}
}
}
/// Data that layout associates with a node.
#[repr(C)]
pub struct PersistentLayoutData {
/// Data accessed by script_layout_interface. This must be first to allow
/// casting between PersistentLayoutData and PartialPersistentLayoutData.
pub base: PartialPersistentLayoutData,
pub struct LayoutData {
/// The current results of flow construction for this node. This is either a
/// flow or a `ConstructionItem`. See comments in `construct.rs` for more
/// details.
@ -29,11 +45,10 @@ pub struct PersistentLayoutData {
pub flags: LayoutDataFlags,
}
impl PersistentLayoutData {
impl LayoutData {
/// Creates new layout data.
pub fn new() -> PersistentLayoutData {
PersistentLayoutData {
base: PartialPersistentLayoutData::new(),
pub fn new() -> LayoutData {
Self {
flow_construction_result: ConstructionResult::None,
before_flow_construction_result: ConstructionResult::None,
after_flow_construction_result: ConstructionResult::None,