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Use a raw pointer instead of the direct JsValue
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Signed-off-by: John Nunley <[email protected]>
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@notgull
notgull committed Sep 2, 2023
1 parent a9fbe05 commit 4711c95
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Showing 2 changed files with 67 additions and 62 deletions.
3 changes: 1 addition & 2 deletions src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -53,8 +53,7 @@ pub use unix::{
WaylandWindowHandle, XcbDisplayHandle, XcbWindowHandle, XlibDisplayHandle, XlibWindowHandle,
};
pub use web::{
Wbg02CanvasWindowHandle, Wbg02Object, Wbg02OffscreenCanvasWindowHandle, WebDisplayHandle,
WebWindowHandle,
Wbg02CanvasWindowHandle, Wbg02OffscreenCanvasWindowHandle, WebDisplayHandle, WebWindowHandle,
};
pub use windows::{Win32WindowHandle, WinRtWindowHandle, WindowsDisplayHandle};

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126 changes: 66 additions & 60 deletions src/web.rs
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Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
use core::fmt;
use core::ffi::c_void;
use core::ptr::NonNull;

/// Raw display handle for the Web.
#[non_exhaustive]
Expand Down Expand Up @@ -69,22 +70,65 @@ pub struct Wbg02CanvasWindowHandle {
/// The object representing the [`HtmlCanvasElement`].
///
/// It is implied that this object is registered in the [`wasm-bindgen`] table and is an instance
/// of [`HtmlCanvasElement`].
/// of [`HtmlCanvasElement`]. The pointer is a direct reference to a [`JsValue`].
///
/// [`HtmlCanvasElement`]: https://docs.rs/web-sys/latest/web_sys/struct.HtmlCanvasElement.html
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
pub obj: Wbg02Object,
/// [`JsValue`]: https://docs.rs/wasm-bindgen/latest/wasm_bindgen/struct.JsValue.html
pub obj: NonNull<c_void>,
}

impl Wbg02CanvasWindowHandle {
/// Create a new handle to an [`HtmlCanvasElement`].
///
/// [`HtmlCanvasElement`]: https://docs.rs/web-sys/latest/web_sys/struct.HtmlCanvasElement.html
pub fn new(obj: Wbg02Object) -> Self {
pub fn new(obj: NonNull<c_void>) -> Self {
Self { obj }
}
}

#[cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02"))]
/// These implementations are only available when `unstable_web_handles_wbg_02` is enabled.
impl Wbg02CanvasWindowHandle {
/// Create a new `Wbg02CanvasWindowHandle` from a [`wasm-bindgen`] object.
///
/// This function is unstable. Its signature may be changed or even removed outright without a
/// breaking version change.
///
/// # Safety
///
/// The [`JsValue`] must refer to an [`HtmlCanvasElement`], and the lifetime must be longer than
/// the `Wbg02CanvasWindowHandle` lives for.
///
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
#[cfg_attr(
docsrs,
doc(cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))
)]
pub unsafe fn from_wasm_bindgen_0_2(js_value: &wasm_bindgen::JsValue) -> Self {
Self::new(NonNull::from(js_value).cast())
}

/// Convert to the underlying [`wasm-bindgen`] index.
///
/// This function is unstable. Its signature may be changed or even removed outright without a
/// breaking version change.
///
/// # Safety
///
/// The lifetime from the `from_wasm_bindgen_0_2` function must still be valid, and the
/// underlying pointer must still be a [`wasm_bindgen`] object.
///
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
#[cfg_attr(
docsrs,
doc(cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))
)]
pub unsafe fn as_wasm_bindgen_0_2(&self) -> &wasm_bindgen::JsValue {
self.obj.cast().as_ref()
}
}

/// Raw window handle for a Web offscreen canvas registered via [`wasm-bindgen`].
///
/// ## Construction
Expand All @@ -103,99 +147,61 @@ pub struct Wbg02OffscreenCanvasWindowHandle {
/// The object representing the [`OffscreenCanvas`].
///
/// It is implied that this object is registered in the [`wasm-bindgen`] table and is an instance
/// of [`OffscreenCanvas`].
/// of [`OffscreenCanvas`]. This is a pointer to the actual [`JsValue`] object.
///
/// [`OffscreenCanvas`]: https://docs.rs/web-sys/latest/web_sys/struct.OffscreenCanvas.html
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
pub obj: Wbg02Object,
/// [`JsValue`]: https://docs.rs/wasm-bindgen/latest/wasm_bindgen/struct.JsValue.html
pub obj: NonNull<c_void>,
}

impl Wbg02OffscreenCanvasWindowHandle {
/// Create a new handle to an [`OffscreenCanvas`].
///
/// [`OffscreenCanvas`]: https://docs.rs/web-sys/latest/web_sys/struct.OffscreenCanvas.html
pub fn new(obj: Wbg02Object) -> Self {
pub fn new(obj: NonNull<c_void>) -> Self {
Self { obj }
}
}

/// An object currently stored in [`wasm-bindgen`].
///
/// This type represents an object stored in the [`wasm-bindgen`] object table. It represents some kind
/// of underlying web object, such as an `HtmlCanvasElement` or an [`OffscreenCanvas`].
///
/// For WASM targets, with the unstable `unstable_web_handles_wbg_02` feature enabled, this type contains
/// an index into the table corresponding to a JavaScript object. In other cases, this type is
/// uninhabited.
///
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
/// [`OffscreenCanvas`]: https://docs.rs/web-sys/latest/web_sys/struct.OffscreenCanvas.html
#[derive(Clone, PartialEq)]
pub struct Wbg02Object {
/// For when `unstable_web_handles_wbg_02` is enabled, this is the index of the object in the
/// `wasm-bindgen` table.
#[cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02"))]
idx: wasm_bindgen::JsValue,

/// In other cases, this type is uninhabited.
#[cfg(not(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))]
_uninhabited: core::convert::Infallible,
}

impl fmt::Debug for Wbg02Object {
fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
#[cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02"))]
{
_f.debug_tuple("Wbg02Object").field(&self.idx).finish()
}

#[cfg(not(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))]
match self._uninhabited {}
}
}

#[cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02"))]
/// These implementations are only available when `unstable_web_handles_wbg_02` is enabled.
impl Wbg02Object {
/// Create a new `Wbg02Object` from a [`wasm-bindgen`] object.
impl Wbg02OffscreenCanvasWindowHandle {
/// Create a new `Wbg02OffscreenCanvasWindowHandle` from a [`wasm-bindgen`] object.
///
/// This function is unstable. Its signature may be changed or even removed outright without a
/// breaking version change.
///
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
#[cfg_attr(
docsrs,
doc(cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))
)]
pub fn new(idx: wasm_bindgen::JsValue) -> Self {
Self { idx }
}

/// Get the index of the object in the [`wasm-bindgen`] table.
/// # Safety
///
/// This function is unstable. Its signature may be changed or even removed outright without a
/// breaking version change.
/// The [`JsValue`] must refer to an [`OffscreenCanvas`], and the lifetime must be longer than
/// the `Wbg02OffscreenCanvasWindowHandle` lives for.
///
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
#[cfg_attr(
docsrs,
doc(cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))
)]
pub fn idx(&self) -> &wasm_bindgen::JsValue {
&self.idx
pub unsafe fn from_wasm_bindgen_0_2(js_value: &wasm_bindgen::JsValue) -> Self {
Self::new(NonNull::from(js_value).cast())
}

/// Convert to the underlying [`wasm-bindgen`] index.
///
/// This function is unstable. Its signature may be changed or even removed outright without a
/// breaking version change.
///
/// # Safety
///
/// The lifetime from the `from_wasm_bindgen_0_2` function must still be valid, and the
/// underlying pointer must still be a [`wasm_bindgen`] object.
///
/// [`wasm-bindgen`]: https://crates.io/crates/wasm-bindgen
#[cfg_attr(
docsrs,
doc(cfg(all(target_family = "wasm", feature = "unstable_web_handles_wbg_02")))
)]
pub fn into_idx(self) -> wasm_bindgen::JsValue {
self.idx
pub unsafe fn as_wasm_bindgen_0_2(&self) -> &wasm_bindgen::JsValue {
self.obj.cast().as_ref()
}
}

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