diff options
Diffstat (limited to 'servo/components/style/gecko_bindings')
9 files changed, 711 insertions, 0 deletions
diff --git a/servo/components/style/gecko_bindings/mod.rs b/servo/components/style/gecko_bindings/mod.rs new file mode 100644 index 0000000000..f0b0adc7ec --- /dev/null +++ b/servo/components/style/gecko_bindings/mod.rs @@ -0,0 +1,28 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Gecko's C++ bindings, along with some rust helpers to ease its use. + +// FIXME: We allow `improper_ctypes` (for now), because the lint doesn't allow +// foreign structs to have `PhantomData`. We should remove this once the lint +// ignores this case. + +#[allow( + dead_code, + improper_ctypes, + non_camel_case_types, + non_snake_case, + non_upper_case_globals, + missing_docs +)] +// TODO: Remove this when updating bindgen, see +// https://github.com/rust-lang/rust-bindgen/issues/1651 +#[cfg_attr(test, allow(deref_nullptr))] +pub mod structs { + include!(concat!(env!("OUT_DIR"), "/gecko/structs.rs")); +} + +pub use self::structs as bindings; + +pub mod sugar; diff --git a/servo/components/style/gecko_bindings/sugar/mod.rs b/servo/components/style/gecko_bindings/sugar/mod.rs new file mode 100644 index 0000000000..00faf63ba6 --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/mod.rs @@ -0,0 +1,13 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Rust sugar and convenience methods for Gecko types. + +mod ns_com_ptr; +mod ns_compatibility; +mod ns_style_auto_array; +mod ns_t_array; +pub mod origin_flags; +pub mod ownership; +pub mod refptr; diff --git a/servo/components/style/gecko_bindings/sugar/ns_com_ptr.rs b/servo/components/style/gecko_bindings/sugar/ns_com_ptr.rs new file mode 100644 index 0000000000..1c54541bd8 --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/ns_com_ptr.rs @@ -0,0 +1,15 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Little helpers for `nsCOMPtr`. + +use crate::gecko_bindings::structs::nsCOMPtr; + +impl<T> nsCOMPtr<T> { + /// Get this pointer as a raw pointer. + #[inline] + pub fn raw(&self) -> *mut T { + self.mRawPtr + } +} diff --git a/servo/components/style/gecko_bindings/sugar/ns_compatibility.rs b/servo/components/style/gecko_bindings/sugar/ns_compatibility.rs new file mode 100644 index 0000000000..f4b81e9f79 --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/ns_compatibility.rs @@ -0,0 +1,19 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Little helper for `nsCompatibility`. + +use crate::context::QuirksMode; +use crate::gecko_bindings::structs::nsCompatibility; + +impl From<nsCompatibility> for QuirksMode { + #[inline] + fn from(mode: nsCompatibility) -> QuirksMode { + match mode { + nsCompatibility::eCompatibility_FullStandards => QuirksMode::NoQuirks, + nsCompatibility::eCompatibility_AlmostStandards => QuirksMode::LimitedQuirks, + nsCompatibility::eCompatibility_NavQuirks => QuirksMode::Quirks, + } + } +} diff --git a/servo/components/style/gecko_bindings/sugar/ns_style_auto_array.rs b/servo/components/style/gecko_bindings/sugar/ns_style_auto_array.rs new file mode 100644 index 0000000000..b5772a6c77 --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/ns_style_auto_array.rs @@ -0,0 +1,111 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Rust helpers for Gecko's `nsStyleAutoArray`. + +use crate::gecko_bindings::bindings::Gecko_EnsureStyleAnimationArrayLength; +use crate::gecko_bindings::bindings::Gecko_EnsureStyleScrollTimelineArrayLength; +use crate::gecko_bindings::bindings::Gecko_EnsureStyleTransitionArrayLength; +use crate::gecko_bindings::bindings::Gecko_EnsureStyleViewTimelineArrayLength; +use crate::gecko_bindings::structs::nsStyleAutoArray; +use crate::gecko_bindings::structs::{StyleAnimation, StyleTransition}; +use crate::gecko_bindings::structs::{StyleScrollTimeline, StyleViewTimeline}; +use std::iter::{once, Chain, IntoIterator, Once}; +use std::ops::{Index, IndexMut}; +use std::slice::{Iter, IterMut}; + +impl<T> Index<usize> for nsStyleAutoArray<T> { + type Output = T; + fn index(&self, index: usize) -> &T { + match index { + 0 => &self.mFirstElement, + _ => &self.mOtherElements[index - 1], + } + } +} + +impl<T> IndexMut<usize> for nsStyleAutoArray<T> { + fn index_mut(&mut self, index: usize) -> &mut T { + match index { + 0 => &mut self.mFirstElement, + _ => &mut self.mOtherElements[index - 1], + } + } +} + +impl<T> nsStyleAutoArray<T> { + /// Mutably iterate over the array elements. + pub fn iter_mut(&mut self) -> Chain<Once<&mut T>, IterMut<T>> { + once(&mut self.mFirstElement).chain(self.mOtherElements.iter_mut()) + } + + /// Iterate over the array elements. + pub fn iter(&self) -> Chain<Once<&T>, Iter<T>> { + once(&self.mFirstElement).chain(self.mOtherElements.iter()) + } + + /// Returns the length of the array. + /// + /// Note that often structs containing autoarrays will have additional + /// member fields that contain the length, which must be kept in sync. + pub fn len(&self) -> usize { + 1 + self.mOtherElements.len() + } +} + +impl nsStyleAutoArray<StyleAnimation> { + /// Ensures that the array has length at least the given length. + pub fn ensure_len(&mut self, len: usize) { + unsafe { + Gecko_EnsureStyleAnimationArrayLength( + self as *mut nsStyleAutoArray<StyleAnimation> as *mut _, + len, + ); + } + } +} + +impl nsStyleAutoArray<StyleTransition> { + /// Ensures that the array has length at least the given length. + pub fn ensure_len(&mut self, len: usize) { + unsafe { + Gecko_EnsureStyleTransitionArrayLength( + self as *mut nsStyleAutoArray<StyleTransition> as *mut _, + len, + ); + } + } +} + +impl nsStyleAutoArray<StyleViewTimeline> { + /// Ensures that the array has length at least the given length. + pub fn ensure_len(&mut self, len: usize) { + unsafe { + Gecko_EnsureStyleViewTimelineArrayLength( + self as *mut nsStyleAutoArray<StyleViewTimeline> as *mut _, + len, + ); + } + } +} + +impl nsStyleAutoArray<StyleScrollTimeline> { + /// Ensures that the array has length at least the given length. + pub fn ensure_len(&mut self, len: usize) { + unsafe { + Gecko_EnsureStyleScrollTimelineArrayLength( + self as *mut nsStyleAutoArray<StyleScrollTimeline> as *mut _, + len, + ); + } + } +} + +impl<'a, T> IntoIterator for &'a mut nsStyleAutoArray<T> { + type Item = &'a mut T; + type IntoIter = Chain<Once<&'a mut T>, IterMut<'a, T>>; + fn into_iter(self) -> Self::IntoIter { + self.iter_mut() + } +} diff --git a/servo/components/style/gecko_bindings/sugar/ns_t_array.rs b/servo/components/style/gecko_bindings/sugar/ns_t_array.rs new file mode 100644 index 0000000000..d10ed420dd --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/ns_t_array.rs @@ -0,0 +1,144 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Rust helpers for Gecko's nsTArray. + +use crate::gecko_bindings::bindings; +use crate::gecko_bindings::structs::{nsTArray, nsTArrayHeader, CopyableTArray}; +use std::mem; +use std::ops::{Deref, DerefMut}; +use std::slice; + +impl<T> Deref for nsTArray<T> { + type Target = [T]; + + #[inline] + fn deref<'a>(&'a self) -> &'a [T] { + unsafe { slice::from_raw_parts(self.slice_begin(), self.header().mLength as usize) } + } +} + +impl<T> DerefMut for nsTArray<T> { + fn deref_mut<'a>(&'a mut self) -> &'a mut [T] { + unsafe { slice::from_raw_parts_mut(self.slice_begin(), self.header().mLength as usize) } + } +} + +impl<T> nsTArray<T> { + #[inline] + fn header<'a>(&'a self) -> &'a nsTArrayHeader { + debug_assert!(!self.mBuffer.is_null()); + unsafe { mem::transmute(self.mBuffer) } + } + + // unsafe, since header may be in shared static or something + unsafe fn header_mut<'a>(&'a mut self) -> &'a mut nsTArrayHeader { + debug_assert!(!self.mBuffer.is_null()); + + mem::transmute(self.mBuffer) + } + + #[inline] + unsafe fn slice_begin(&self) -> *mut T { + debug_assert!(!self.mBuffer.is_null()); + (self.mBuffer as *const nsTArrayHeader).offset(1) as *mut _ + } + + /// Ensures the array has enough capacity at least to hold `cap` elements. + /// + /// NOTE: This doesn't call the constructor on the values! + pub fn ensure_capacity(&mut self, cap: usize) { + if cap >= self.len() { + unsafe { + bindings::Gecko_EnsureTArrayCapacity( + self as *mut nsTArray<T> as *mut _, + cap, + mem::size_of::<T>(), + ) + } + } + } + + /// Clears the array storage without calling the destructor on the values. + #[inline] + pub unsafe fn clear(&mut self) { + if self.len() != 0 { + bindings::Gecko_ClearPODTArray( + self as *mut nsTArray<T> as *mut _, + mem::size_of::<T>(), + mem::align_of::<T>(), + ); + } + } + + /// Clears a POD array. This is safe since copy types are memcopyable. + #[inline] + pub fn clear_pod(&mut self) + where + T: Copy, + { + unsafe { self.clear() } + } + + /// Resize and set the length of the array to `len`. + /// + /// unsafe because this may leave the array with uninitialized elements. + /// + /// This will not call constructors. If you need that, either manually add + /// bindings or run the typed `EnsureCapacity` call on the gecko side. + pub unsafe fn set_len(&mut self, len: u32) { + // this can leak + debug_assert!(len >= self.len() as u32); + if self.len() == len as usize { + return; + } + self.ensure_capacity(len as usize); + self.header_mut().mLength = len; + } + + /// Resizes an array containing only POD elements + /// + /// unsafe because this may leave the array with uninitialized elements. + /// + /// This will not leak since it only works on POD types (and thus doesn't assert) + pub unsafe fn set_len_pod(&mut self, len: u32) + where + T: Copy, + { + if self.len() == len as usize { + return; + } + self.ensure_capacity(len as usize); + let header = self.header_mut(); + header.mLength = len; + } + + /// Collects the given iterator into this array. + /// + /// Not unsafe because we won't leave uninitialized elements in the array. + pub fn assign_from_iter_pod<I>(&mut self, iter: I) + where + T: Copy, + I: ExactSizeIterator + Iterator<Item = T>, + { + debug_assert!(iter.len() <= 0xFFFFFFFF); + unsafe { + self.set_len_pod(iter.len() as u32); + } + self.iter_mut().zip(iter).for_each(|(r, v)| *r = v); + } +} + +impl<T> Deref for CopyableTArray<T> { + type Target = nsTArray<T>; + fn deref(&self) -> &Self::Target { + &self._base + } +} + +impl<T> DerefMut for CopyableTArray<T> { + fn deref_mut(&mut self) -> &mut nsTArray<T> { + &mut self._base + } +} diff --git a/servo/components/style/gecko_bindings/sugar/origin_flags.rs b/servo/components/style/gecko_bindings/sugar/origin_flags.rs new file mode 100644 index 0000000000..b27060405a --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/origin_flags.rs @@ -0,0 +1,31 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Helper to iterate over `OriginFlags` bits. + +use crate::gecko_bindings::structs::OriginFlags; +use crate::stylesheets::OriginSet; + +/// Checks that the values for OriginFlags are the ones we expect. +pub fn assert_flags_match() { + use crate::stylesheets::origin::*; + debug_assert_eq!( + OriginFlags::UserAgent.0, + OriginSet::ORIGIN_USER_AGENT.bits() + ); + debug_assert_eq!(OriginFlags::Author.0, OriginSet::ORIGIN_AUTHOR.bits()); + debug_assert_eq!(OriginFlags::User.0, OriginSet::ORIGIN_USER.bits()); +} + +impl From<OriginFlags> for OriginSet { + fn from(flags: OriginFlags) -> Self { + Self::from_bits_retain(flags.0) + } +} + +impl From<OriginSet> for OriginFlags { + fn from(set: OriginSet) -> Self { + OriginFlags(set.bits()) + } +} diff --git a/servo/components/style/gecko_bindings/sugar/ownership.rs b/servo/components/style/gecko_bindings/sugar/ownership.rs new file mode 100644 index 0000000000..31b512cf1e --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/ownership.rs @@ -0,0 +1,61 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! Helpers for different FFI pointer kinds that Gecko's FFI layer uses. + +use crate::gecko_bindings::structs::root::mozilla::detail::CopyablePtr; +use servo_arc::Arc; +use std::marker::PhantomData; +use std::ops::{Deref, DerefMut}; +use std::ptr; + +/// Gecko-FFI-safe Arc (T is an ArcInner). +/// +/// This can be null. +/// +/// Leaks on drop. Please don't drop this. +#[repr(C)] +pub struct Strong<GeckoType> { + ptr: *const GeckoType, + _marker: PhantomData<GeckoType>, +} + +impl<T> From<Arc<T>> for Strong<T> { + fn from(arc: Arc<T>) -> Self { + Self { + ptr: Arc::into_raw(arc), + _marker: PhantomData, + } + } +} + +impl<GeckoType> Strong<GeckoType> { + #[inline] + /// Returns whether this reference is null. + pub fn is_null(&self) -> bool { + self.ptr.is_null() + } + + #[inline] + /// Returns a null pointer + pub fn null() -> Self { + Self { + ptr: ptr::null(), + _marker: PhantomData, + } + } +} + +impl<T> Deref for CopyablePtr<T> { + type Target = T; + fn deref(&self) -> &Self::Target { + &self.mPtr + } +} + +impl<T> DerefMut for CopyablePtr<T> { + fn deref_mut<'a>(&'a mut self) -> &'a mut T { + &mut self.mPtr + } +} diff --git a/servo/components/style/gecko_bindings/sugar/refptr.rs b/servo/components/style/gecko_bindings/sugar/refptr.rs new file mode 100644 index 0000000000..c4a0479a07 --- /dev/null +++ b/servo/components/style/gecko_bindings/sugar/refptr.rs @@ -0,0 +1,289 @@ +/* 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 https://mozilla.org/MPL/2.0/. */ + +//! A rust helper to ease the use of Gecko's refcounted types. + +use crate::gecko_bindings::{bindings, structs}; +use crate::Atom; +use servo_arc::Arc; +use std::fmt::Write; +use std::marker::PhantomData; +use std::ops::Deref; +use std::{fmt, mem, ptr}; + +/// Trait for all objects that have Addref() and Release +/// methods and can be placed inside RefPtr<T> +pub unsafe trait RefCounted { + /// Bump the reference count. + fn addref(&self); + /// Decrease the reference count. + unsafe fn release(&self); +} + +/// Trait for types which can be shared across threads in RefPtr. +pub unsafe trait ThreadSafeRefCounted: RefCounted {} + +/// A custom RefPtr implementation to take into account Drop semantics and +/// a bit less-painful memory management. +pub struct RefPtr<T: RefCounted> { + ptr: *mut T, + _marker: PhantomData<T>, +} + +impl<T: RefCounted> fmt::Debug for RefPtr<T> { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + f.write_str("RefPtr { ")?; + self.ptr.fmt(f)?; + f.write_char('}') + } +} + +impl<T: RefCounted> RefPtr<T> { + /// Create a new RefPtr from an already addrefed pointer obtained from FFI. + /// + /// The pointer must be valid, non-null and have been addrefed. + pub unsafe fn from_addrefed(ptr: *mut T) -> Self { + debug_assert!(!ptr.is_null()); + RefPtr { + ptr, + _marker: PhantomData, + } + } + + /// Returns whether the current pointer is null. + pub fn is_null(&self) -> bool { + self.ptr.is_null() + } + + /// Returns a null pointer. + pub fn null() -> Self { + Self { + ptr: ptr::null_mut(), + _marker: PhantomData, + } + } + + /// Create a new RefPtr from a pointer obtained from FFI. + /// + /// This method calls addref() internally + pub unsafe fn new(ptr: *mut T) -> Self { + let ret = RefPtr { + ptr, + _marker: PhantomData, + }; + ret.addref(); + ret + } + + /// Produces an FFI-compatible RefPtr that can be stored in style structs. + /// + /// structs::RefPtr does not have a destructor, so this may leak + pub fn forget(self) -> structs::RefPtr<T> { + let ret = structs::RefPtr { + mRawPtr: self.ptr, + _phantom_0: PhantomData, + }; + mem::forget(self); + ret + } + + /// Returns the raw inner pointer to be fed back into FFI. + pub fn get(&self) -> *mut T { + self.ptr + } + + /// Addref the inner data, obviously leaky on its own. + pub fn addref(&self) { + if !self.ptr.is_null() { + unsafe { + (*self.ptr).addref(); + } + } + } + + /// Release the inner data. + /// + /// Call only when the data actually needs releasing. + pub unsafe fn release(&self) { + if !self.ptr.is_null() { + (*self.ptr).release(); + } + } +} + +impl<T: RefCounted> Deref for RefPtr<T> { + type Target = T; + fn deref(&self) -> &T { + debug_assert!(!self.ptr.is_null()); + unsafe { &*self.ptr } + } +} + +impl<T: RefCounted> structs::RefPtr<T> { + /// Produces a Rust-side RefPtr from an FFI RefPtr, bumping the refcount. + /// + /// Must be called on a valid, non-null structs::RefPtr<T>. + pub unsafe fn to_safe(&self) -> RefPtr<T> { + let r = RefPtr { + ptr: self.mRawPtr, + _marker: PhantomData, + }; + r.addref(); + r + } + /// Produces a Rust-side RefPtr, consuming the existing one (and not bumping + /// the refcount). + pub unsafe fn into_safe(self) -> RefPtr<T> { + debug_assert!(!self.mRawPtr.is_null()); + RefPtr { + ptr: self.mRawPtr, + _marker: PhantomData, + } + } + + /// Replace a structs::RefPtr<T> with a different one, appropriately + /// addref/releasing. + /// + /// Both `self` and `other` must be valid, but can be null. + /// + /// Safe when called on an aliased pointer because the refcount in that case + /// needs to be at least two. + pub unsafe fn set(&mut self, other: &Self) { + self.clear(); + if !other.mRawPtr.is_null() { + *self = other.to_safe().forget(); + } + } + + /// Clear an instance of the structs::RefPtr<T>, by releasing + /// it and setting its contents to null. + /// + /// `self` must be valid, but can be null. + pub unsafe fn clear(&mut self) { + if !self.mRawPtr.is_null() { + (*self.mRawPtr).release(); + self.mRawPtr = ptr::null_mut(); + } + } + + /// Replace a `structs::RefPtr<T>` with a `RefPtr<T>`, + /// consuming the `RefPtr<T>`, and releasing the old + /// value in `self` if necessary. + /// + /// `self` must be valid, possibly null. + pub fn set_move(&mut self, other: RefPtr<T>) { + if !self.mRawPtr.is_null() { + unsafe { + (*self.mRawPtr).release(); + } + } + *self = other.forget(); + } +} + +impl<T> structs::RefPtr<T> { + /// Returns a new, null refptr. + pub fn null() -> Self { + Self { + mRawPtr: ptr::null_mut(), + _phantom_0: PhantomData, + } + } + + /// Create a new RefPtr from an arc. + pub fn from_arc(s: Arc<T>) -> Self { + Self { + mRawPtr: Arc::into_raw(s) as *mut _, + _phantom_0: PhantomData, + } + } + + /// Sets the contents to an Arc<T>. + pub fn set_arc(&mut self, other: Arc<T>) { + unsafe { + if !self.mRawPtr.is_null() { + let _ = Arc::from_raw(self.mRawPtr); + } + self.mRawPtr = Arc::into_raw(other) as *mut _; + } + } +} + +impl<T: RefCounted> Drop for RefPtr<T> { + fn drop(&mut self) { + unsafe { self.release() } + } +} + +impl<T: RefCounted> Clone for RefPtr<T> { + fn clone(&self) -> Self { + self.addref(); + RefPtr { + ptr: self.ptr, + _marker: PhantomData, + } + } +} + +impl<T: RefCounted> PartialEq for RefPtr<T> { + fn eq(&self, other: &Self) -> bool { + self.ptr == other.ptr + } +} + +unsafe impl<T: ThreadSafeRefCounted> Send for RefPtr<T> {} +unsafe impl<T: ThreadSafeRefCounted> Sync for RefPtr<T> {} + +macro_rules! impl_refcount { + ($t:ty, $addref:path, $release:path) => { + unsafe impl RefCounted for $t { + #[inline] + fn addref(&self) { + unsafe { $addref(self as *const _ as *mut _) } + } + + #[inline] + unsafe fn release(&self) { + $release(self as *const _ as *mut _) + } + } + }; +} + +// Companion of NS_DECL_THREADSAFE_FFI_REFCOUNTING. +// +// Gets you a free RefCounted impl implemented via FFI. +macro_rules! impl_threadsafe_refcount { + ($t:ty, $addref:path, $release:path) => { + impl_refcount!($t, $addref, $release); + unsafe impl ThreadSafeRefCounted for $t {} + }; +} + +impl_threadsafe_refcount!( + structs::mozilla::URLExtraData, + bindings::Gecko_AddRefURLExtraDataArbitraryThread, + bindings::Gecko_ReleaseURLExtraDataArbitraryThread +); +impl_threadsafe_refcount!( + structs::nsIURI, + bindings::Gecko_AddRefnsIURIArbitraryThread, + bindings::Gecko_ReleasensIURIArbitraryThread +); +impl_threadsafe_refcount!( + structs::SheetLoadDataHolder, + bindings::Gecko_AddRefSheetLoadDataHolderArbitraryThread, + bindings::Gecko_ReleaseSheetLoadDataHolderArbitraryThread +); + +#[inline] +unsafe fn addref_atom(atom: *mut structs::nsAtom) { + mem::forget(Atom::from_raw(atom)); +} + +#[inline] +unsafe fn release_atom(atom: *mut structs::nsAtom) { + let _ = Atom::from_addrefed(atom); +} +impl_threadsafe_refcount!(structs::nsAtom, addref_atom, release_atom); |