Many WebGL objects refer to a `WebGLRenderingContext` and rely on it for
messaging to the `WebGLThread`. This poses a problem, because WebGL
objects often need to send a message to the `WebGLThread` during their
`Drop` implementation. If the `Drop` is triggered as part of garbage
collection, references to the `WebGLRenderingContext` might be invalid,
if they were garbage collected first as part of the same harvest.
This change makes it so that all of these objects store a `WeakRef`
instead of a `Dom<>`. The `WeakRef` is only used if it can be rooted,
otherwise a `ContextLost` error is given. In cases where only messaging
is needed, a cloned `WebGLMsgSender` is used to perform messages
regardless of whether the context is garbage collected or not.
This isn't a replacement for #37622, but should make it easier to
implement as
the `WebGLMsgSender` and the `WeakRef` could be stored in the droppable
portion of the DOM object.
Testing: This fixes a use-after-free issue which is mainly detectable
via ASAN
builds. Since we do not run ASAN on CI, this is a bit hard to create
automated
tests for. I verified that this fixed the issue manually.
Fixes: #40655.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This implements LazyDOMString (from now on DOMString) as outlined in
https://github.com/servo/servo/issues/39479.
Constructing from a *mut JSString we keep the in a
RootedTraceableBox<Heap<*mut JSString>> and transform
the string into a rust string if necessary via the `make_rust_string`
method.
Methods used in script are implemented on this string. Currently we
transform the string at all times.
But in the future more efficient implementations are possible.
We implement the safety critical sections in a separate module
DOMStringInner which allows simple constructors, `make_rust_string` and
the `bytes` method.
This method returns the new type `EncodedBytes` which contains the
reference to the underlying string in either format.
Testing: WPT tests still seem to work, so this should test this
functionality.
---------
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
This is part of the future work of implementing LazyDOMString as
outlined in issue #39479.
We use str() method or direct implementations on DOMString for these
methods. We also change some types.
This is independent of https://github.com/servo/servo/pull/39480
Signed-off-by: Narfinger Narfinger@users.noreply.github.com
Testing: This is essentially just renaming a method and a type and
should not change functionality.
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
This should be the final PR for the Hash Function series that is
trivial.
Of note: I decided to transform `HashMapTracedValues<Atom,..>` to use
FxBuildHasher. This is likely not going to improve performance as Atom's
already have a unique u32 that is used as the Hash but it safes a few
bytes for the RandomState that is normally in the HashMap.
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
Testing: Hash function changes should not change functionality, we
slightly decrease the size and unit tests still work.
Signed-off-by: Narfinger <Narfinger@users.noreply.github.com>
Move interfaces defined by the WebGL spec to the `script/dom/webgl/
`module from `script/dom/`.
`script/dom/webgl*.rs` -> `script/dom/webgl/`
`script/dom/webgl_extensions` -> `script/dom/webgl/extensions`
`script/dom/webgl_validations` -> `script/dom/webgl/validations`
Testing: No changes, just a refactoring
Fixes (partially): #38901
Signed-off-by: Andrei Volykhin <volykhin.andrei@huawei.com>
Co-authored-by: Andrei Volykhin <volykhin.andrei@huawei.com>
