Bug 1474793 - Part 11: Add FFI API to use SharedMemoryBuilder. r=emilio

Depends on D17197

Differential Revision: https://phabricator.services.mozilla.com/D17198

--HG--
extra : moz-landing-system : lando

Cargo.lock

@@ -1187,6 +1187,7 @@ dependencies = [
  "smallvec 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "style_traits 0.0.1",
+ "to_shmem 0.0.1",
 ]
 
 [[package]]
@@ -2792,6 +2793,7 @@ dependencies = [
  "smallvec 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "style 0.0.1",
  "style_traits 0.0.1",
+ "to_shmem 0.0.1",
 ]
 
 [[package]]

layout/style/ServoBindingTypes.h

@@ -180,6 +180,7 @@ SERVO_ARC_TYPE(ComputedStyle, mozilla::ComputedStyle)
 SERVO_BOXED_TYPE(StyleSet, RawServoStyleSet)
 SERVO_BOXED_TYPE(AuthorStyles, RawServoAuthorStyles)
 SERVO_BOXED_TYPE(SelectorList, RawServoSelectorList)
+SERVO_BOXED_TYPE(SharedMemoryBuilder, RawServoSharedMemoryBuilder)
 SERVO_BOXED_TYPE(SourceSizeList, RawServoSourceSizeList)
 SERVO_BOXED_TYPE(UseCounters, StyleUseCounters)
 #undef SERVO_BOXED_TYPE

layout/style/ServoBindings.h

@@ -1002,6 +1002,16 @@ void Servo_Quotes_GetQuote(const RawServoQuotes* quotes, int32_t depth,
                            mozilla::StyleContentType quote_type,
                            nsAString* result);
 
+RawServoSharedMemoryBuilder* Servo_SharedMemoryBuilder_Create(uint8_t* buffer,
+                                                              size_t len);
+
+const ServoCssRules* Servo_SharedMemoryBuilder_AddStylesheet(
+    RawServoSharedMemoryBuilder* builder,
+    const RawServoStyleSheetContents* sheet);
+
+size_t Servo_SharedMemoryBuilder_GetLength(
+    RawServoSharedMemoryBuilder* builder);
+
 }  // extern "C"
 
 #pragma GCC diagnostic pop

servo/components/style/gecko/boxed_types.rs

@@ -0,0 +1,21 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+//! FFI implementations for types listed in ServoBoxedTypeList.h.
+
+use crate::gecko_bindings::sugar::ownership::{HasBoxFFI, HasFFI, HasSimpleFFI};
+use to_shmem::SharedMemoryBuilder;
+
+// TODO(heycam): The FFI impls for most of the types in ServoBoxedTypeList.h are spread across
+// various files at the moment, but should probably all move here, and use macros to define
+// them more succinctly, like we do in arc_types.rs.
+
+#[cfg(feature = "gecko")]
+unsafe impl HasFFI for SharedMemoryBuilder {
+    type FFIType = crate::gecko_bindings::bindings::RawServoSharedMemoryBuilder;
+}
+#[cfg(feature = "gecko")]
+unsafe impl HasSimpleFFI for SharedMemoryBuilder {}
+#[cfg(feature = "gecko")]
+unsafe impl HasBoxFFI for SharedMemoryBuilder {}

servo/components/style/gecko/mod.rs

@@ -8,6 +8,7 @@
 mod non_ts_pseudo_class_list;
 
 pub mod arc_types;
+pub mod boxed_types;
 pub mod conversions;
 pub mod data;
 pub mod media_features;

servo/ports/geckolib/Cargo.toml

@@ -27,3 +27,4 @@ servo_arc = {path = "../../components/servo_arc"}
 smallvec = "0.6"
 style = {path = "../../components/style", features = ["gecko"]}
 style_traits = {path = "../../components/style_traits"}
+to_shmem = {path = "../../components/to_shmem"}

servo/ports/geckolib/glue.rs

@@ -55,7 +55,8 @@ use style::gecko_bindings::structs::{
     RawServoKeyframesRule, ServoCssRules, RawServoStyleSheetContents,
     RawServoPageRule, RawServoNamespaceRule, RawServoMozDocumentRule,
     RawServoKeyframe, RawServoMediaRule, RawServoImportRule,
-    RawServoFontFaceRule, RawServoFontFeatureValuesRule
+    RawServoFontFaceRule, RawServoFontFeatureValuesRule,
+    RawServoSharedMemoryBuilder
 };
 use style::gecko_bindings::structs::gfxFontFeatureValueSet;
 use style::gecko_bindings::structs::nsAtom;
@@ -107,7 +108,7 @@ use style::properties::{parse_one_declaration_into, parse_style_attribute};
 use style::properties::{ComputedValues, Importance, NonCustomPropertyId};
 use style::properties::{LonghandId, LonghandIdSet, PropertyDeclarationBlock, PropertyId};
 use style::properties::{PropertyDeclarationId, ShorthandId};
-use style::properties::{SourcePropertyDeclaration, StyleBuilder};
+use style::properties::{SourcePropertyDeclaration, StyleBuilder, UnparsedValue};
 use style::rule_cache::RuleCacheConditions;
 use style::rule_tree::{CascadeLevel, StrongRuleNode};
 use style::selector_parser::{PseudoElementCascadeType, SelectorImpl};
@@ -137,6 +138,7 @@ use style::values::specified::gecko::IntersectionObserverRootMargin;
 use style::values::specified::source_size_list::SourceSizeList;
 use style::values::{CustomIdent, KeyframesName};
 use style_traits::{CssWriter, ParsingMode, StyleParseErrorKind, ToCss};
+use to_shmem::SharedMemoryBuilder;
 
 trait ClosureHelper {
     fn invoke(&self);
@@ -6337,3 +6339,55 @@ pub unsafe extern "C" fn Servo_Quotes_GetQuote(
     };
     (*result).write_str(quote).unwrap();
 }
+
+#[no_mangle]
+pub unsafe extern "C" fn Servo_SharedMemoryBuilder_Create(
+    buffer: *mut u8,
+    len: usize,
+) -> *mut RawServoSharedMemoryBuilder {
+    let mut builder = Box::new(SharedMemoryBuilder::new(buffer, len));
+
+    // We have Arc<UnparsedValue>s in style sheets due to CSS variables being
+    // used in shorthand property declarations.  There aren't many, though,
+    // and they aren't big, so we just allow their duplication for now.
+    builder.add_allowed_duplication_type::<UnparsedValue>();
+
+    Box::into_raw(builder) as *mut _
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Servo_SharedMemoryBuilder_AddStylesheet(
+    builder: &mut RawServoSharedMemoryBuilder,
+    raw_contents: &RawServoStyleSheetContents,
+) -> *const ServoCssRules {
+    let builder = SharedMemoryBuilder::from_ffi_mut(builder);
+    let contents = StylesheetContents::as_arc(&raw_contents);
+
+    // Assert some things we assume when we create a style sheet from shared
+    // memory.
+    debug_assert_eq!(contents.origin, Origin::UserAgent);
+    debug_assert_eq!(contents.quirks_mode, QuirksMode::NoQuirks);
+    debug_assert!(contents.source_map_url.read().is_none());
+    debug_assert!(contents.source_url.read().is_none());
+
+    let rules = &contents.rules;
+    let shared_rules: &Arc<Locked<CssRules>> = &*builder.write(rules);
+    (&*shared_rules).with_raw_offset_arc(|arc| {
+        *Locked::<CssRules>::arc_as_borrowed(arc) as *const _
+    })
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Servo_SharedMemoryBuilder_GetLength(
+    builder: &mut RawServoSharedMemoryBuilder,
+) -> usize {
+    let builder = SharedMemoryBuilder::from_ffi_mut(builder);
+    builder.len()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn Servo_SharedMemoryBuilder_Drop(
+    builder: Owned<RawServoSharedMemoryBuilder>
+) {
+    let _ = builder.into_box::<SharedMemoryBuilder>();
+}

servo/ports/geckolib/lib.rs

@@ -17,6 +17,7 @@ extern crate smallvec;
 #[macro_use]
 extern crate style;
 extern crate style_traits;
+extern crate to_shmem;
 
 mod error_reporter;
 #[allow(non_snake_case)]

servo/ports/geckolib/tests/Cargo.toml

@@ -24,3 +24,4 @@ size_of_test = {path = "../../../components/size_of_test"}
 smallvec = "0.6"
 style_traits = {path = "../../../components/style_traits"}
 style = {path = "../../../components/style", features = ["gecko"]}
+to_shmem = {path = "../../../components/to_shmem"}

servo/ports/geckolib/tests/lib.rs

@@ -26,6 +26,7 @@ extern crate size_of_test;
 #[cfg_attr(target_pointer_width = "64", macro_use)]
 extern crate style;
 extern crate style_traits;
+extern crate to_shmem;
 
 #[cfg(target_pointer_width = "64")]
 mod size_of;

servo/tests/unit/style/Cargo.toml

@@ -27,3 +27,4 @@ size_of_test = {path = "../../../components/size_of_test"}
 style = {path = "../../../components/style"}
 style_traits = {path = "../../../components/style_traits"}
 std_test_override = { path = "../../../components/std_test_override" }
+to_shmem = { path = "../../../components/to_shmem" }