Auto merge of #15682 - upsuper:arc-types, r=Manishearth

Simplify defining arc ffi types

r? @Manishearth

I don't have a good sense for creating syntax... so if you have any suggestion for the syntax of `impl_arc_ffi` macro, it would be appreciated.

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components/style/gecko/arc_types.rs

@@ -0,0 +1,58 @@
+/* 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/. */
+
+//! This file lists all arc FFI types and defines corresponding addref
+//! and release functions. This list corresponds to ServoArcTypeList.h
+//! file in Gecko.
+
+#![allow(non_snake_case, missing_docs)]
+
+use gecko_bindings::bindings::{RawServoStyleSheet, RawServoStyleRule, RawServoImportRule};
+use gecko_bindings::bindings::{ServoComputedValues, ServoCssRules};
+use gecko_bindings::structs::{RawServoAnimationValue, RawServoDeclarationBlock};
+use gecko_bindings::sugar::ownership::{HasArcFFI, HasFFI};
+use parking_lot::RwLock;
+use properties::{ComputedValues, PropertyDeclarationBlock};
+use properties::animated_properties::AnimationValue;
+use stylesheets::{CssRules, Stylesheet, StyleRule, ImportRule};
+
+macro_rules! impl_arc_ffi {
+    ($servo_type:ty => $gecko_type:ty [$addref:ident, $release:ident]) => {
+        unsafe impl HasFFI for $servo_type {
+            type FFIType = $gecko_type;
+        }
+        unsafe impl HasArcFFI for $servo_type {}
+
+        #[no_mangle]
+        pub unsafe extern "C" fn $addref(obj: &$gecko_type) -> () {
+            <$servo_type>::addref(obj);
+        }
+
+        #[no_mangle]
+        pub unsafe extern "C" fn $release(obj: &$gecko_type) -> () {
+            <$servo_type>::release(obj);
+        }
+    }
+}
+
+impl_arc_ffi!(RwLock<CssRules> => ServoCssRules
+              [Servo_CssRules_AddRef, Servo_CssRules_Release]);
+
+impl_arc_ffi!(Stylesheet => RawServoStyleSheet
+              [Servo_StyleSheet_AddRef, Servo_StyleSheet_Release]);
+
+impl_arc_ffi!(ComputedValues => ServoComputedValues
+              [Servo_ComputedValues_AddRef, Servo_ComputedValues_Release]);
+
+impl_arc_ffi!(RwLock<PropertyDeclarationBlock> => RawServoDeclarationBlock
+              [Servo_DeclarationBlock_AddRef, Servo_DeclarationBlock_Release]);
+
+impl_arc_ffi!(RwLock<StyleRule> => RawServoStyleRule
+              [Servo_StyleRule_AddRef, Servo_StyleRule_Release]);
+
+impl_arc_ffi!(RwLock<ImportRule> => RawServoImportRule
+              [Servo_ImportRule_AddRef, Servo_ImportRule_Release]);
+
+impl_arc_ffi!(AnimationValue => RawServoAnimationValue
+              [Servo_AnimationValue_AddRef, Servo_AnimationValue_Release]);

components/style/gecko/conversions.rs

@@ -11,47 +11,12 @@
 use app_units::Au;
 use gecko::values::convert_rgba_to_nscolor;
 use gecko_bindings::bindings::{Gecko_CreateGradient, Gecko_SetGradientImageValue, Gecko_SetUrlImageValue};
-use gecko_bindings::bindings::{RawServoStyleSheet, RawServoStyleRule, RawServoImportRule};
-use gecko_bindings::bindings::{ServoComputedValues, ServoCssRules};
 use gecko_bindings::structs::{nsStyleCoord_CalcValue, nsStyleImage};
-use gecko_bindings::structs::RawServoDeclarationBlock;
 use gecko_bindings::structs::nsresult;
 use gecko_bindings::sugar::ns_style_coord::{CoordDataValue, CoordDataMut};
-use gecko_bindings::sugar::ownership::{HasArcFFI, HasFFI};
-use parking_lot::RwLock;
-use properties::{ComputedValues, PropertyDeclarationBlock};
-use stylesheets::{CssRules, RulesMutateError, Stylesheet, StyleRule, ImportRule};
+use stylesheets::RulesMutateError;
 use values::computed::{CalcLengthOrPercentage, Gradient, Image, LengthOrPercentage, LengthOrPercentageOrAuto};
 
-unsafe impl HasFFI for Stylesheet {
-    type FFIType = RawServoStyleSheet;
-}
-unsafe impl HasArcFFI for Stylesheet {}
-unsafe impl HasFFI for ComputedValues {
-    type FFIType = ServoComputedValues;
-}
-unsafe impl HasArcFFI for ComputedValues {}
-
-unsafe impl HasFFI for RwLock<PropertyDeclarationBlock> {
-    type FFIType = RawServoDeclarationBlock;
-}
-unsafe impl HasArcFFI for RwLock<PropertyDeclarationBlock> {}
-
-unsafe impl HasFFI for RwLock<CssRules> {
-    type FFIType = ServoCssRules;
-}
-unsafe impl HasArcFFI for RwLock<CssRules> {}
-
-unsafe impl HasFFI for RwLock<StyleRule> {
-    type FFIType = RawServoStyleRule;
-}
-unsafe impl HasArcFFI for RwLock<StyleRule> {}
-
-unsafe impl HasFFI for RwLock<ImportRule> {
-    type FFIType = RawServoImportRule;
-}
-unsafe impl HasArcFFI for RwLock<ImportRule> {}
-
 impl From<CalcLengthOrPercentage> for nsStyleCoord_CalcValue {
     fn from(other: CalcLengthOrPercentage) -> nsStyleCoord_CalcValue {
         let has_percentage = other.percentage.is_some();

components/style/gecko/mod.rs

@@ -4,6 +4,7 @@
 
 //! Gecko-specific style-system bits.
 
+pub mod arc_types;
 pub mod conversions;
 pub mod data;
 pub mod media_queries;

components/style/properties/helpers/animated_properties.mako.rs

@@ -232,17 +232,6 @@ impl AnimatedProperty {
     }
 }
 
-
-% if product == "gecko":
-    use gecko_bindings::structs::RawServoAnimationValue;
-    use gecko_bindings::sugar::ownership::{HasArcFFI, HasFFI};
-
-    unsafe impl HasFFI for AnimationValue {
-        type FFIType = RawServoAnimationValue;
-    }
-    unsafe impl HasArcFFI for AnimationValue {}
-% endif
-
 /// An enum to represent a single computed value belonging to an animated
 /// property in order to be interpolated with another one. When interpolating,
 /// both values need to belong to the same property.