diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs index 747573cec05..0cbb49bea3e 100644 --- a/components/script/dom/bindings/conversions.rs +++ b/components/script/dom/bindings/conversions.rs @@ -37,6 +37,7 @@ use dom::bindings::js::Root; use dom::bindings::num::Finite; use dom::bindings::reflector::{DomObject, Reflector}; use dom::bindings::str::{ByteString, DOMString, USVString}; +use dom::bindings::trace::{JSTraceable, RootedTraceableBox}; use dom::bindings::utils::DOMClass; use js; pub use js::conversions::{FromJSValConvertible, ToJSValConvertible, ConversionResult}; @@ -117,6 +118,22 @@ impl FromJSValConvertible for Root { } } +impl FromJSValConvertible for RootedTraceableBox { + type Config = T::Config; + + unsafe fn from_jsval(cx: *mut JSContext, + value: HandleValue, + config: Self::Config) + -> Result, ()> { + T::from_jsval(cx, value, config).map(|result| { + match result { + ConversionResult::Success(v) => ConversionResult::Success(RootedTraceableBox::new(v)), + ConversionResult::Failure(e) => ConversionResult::Failure(e), + } + }) + } +} + /// Convert `id` to a `DOMString`, assuming it is string-valued. /// /// Handling of invalid UTF-16 in strings depends on the relevant option. diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs index 763ccb9b22b..aeddcdabe4b 100644 --- a/components/script/dom/bindings/trace.rs +++ b/components/script/dom/bindings/trace.rs @@ -653,6 +653,61 @@ impl<'a, T: JSTraceable + 'static> Drop for RootedTraceable<'a, T> { } } +/// Roots any JSTraceable thing +/// +/// If you have a valid DomObject, use Root. +/// If you have GC things like *mut JSObject or JSVal, use rooted!. +/// If you have an arbitrary number of DomObjects to root, use rooted_vec!. +/// If you know what you're doing, use this. +pub struct RootedTraceableBox { + ptr: *mut T, +} + +unsafe impl JSTraceable for RootedTraceableBox { + unsafe fn trace(&self, tracer: *mut JSTracer) { + (*self.ptr).trace(tracer); + } +} + +impl RootedTraceableBox { + /// Root a JSTraceable thing for the life of this RootedTraceable + pub fn new(traceable: T) -> RootedTraceableBox { + let traceable = Box::into_raw(box traceable); + unsafe { + RootedTraceableSet::add(traceable); + } + RootedTraceableBox { + ptr: traceable, + } + } +} + +impl Deref for RootedTraceableBox { + type Target = T; + fn deref(&self) -> &T { + unsafe { + &*self.ptr + } + } +} + +impl DerefMut for RootedTraceableBox { + fn deref_mut(&mut self) -> &mut T { + unsafe { + &mut *self.ptr + } + } +} + +impl Drop for RootedTraceableBox { + fn drop(&mut self) { + unsafe { + RootedTraceableSet::remove(self.ptr); + let _ = Box::from_raw(self.ptr); + } + } +} + /// A vector of items to be rooted with `RootedVec`. /// Guaranteed to be empty when not rooted. /// Usage: `rooted_vec!(let mut v);` or if you have an