Auto merge of #10359 - bholley:style_struct_management, r=SimonSapin

Implement construction, destruction, and copying of gecko style structs

This requires some new machinery on the gecko side, which I'll get up in bugzilla shortly.

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5 files changed, 192 insertions, 18 deletions

diff --git a/components/style/properties.mako.rs b/components/style/properties.mako.rs
index ce285c4d71b..0b9dcd11217 100644
--- a/components/style/properties.mako.rs
+++ b/components/style/properties.mako.rs
@@ -6722,10 +6722,8 @@ pub type CascadePropertyFn<C /*: ComputedValues */> =
                      cacheable: &mut bool,
                      error_reporter: &mut Box<ParseErrorReporter + Send>);
 
-// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
-// properties.
-thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = {
-    let mut result: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = Vec::new();
+pub fn make_cascade_vec<C: ComputedValues>() -> Vec<Option<CascadePropertyFn<C>>> {
+    let mut result: Vec<Option<CascadePropertyFn<C>>> = Vec::new();
     % for style_struct in STYLE_STRUCTS:
         % for property in style_struct.longhands:
             let discriminant;
@@ -6741,6 +6739,12 @@ thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoCompute
         % endfor
     % endfor
     result
+}
+
+// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
+// properties.
+thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<ServoComputedValues>>> = {
+    make_cascade_vec::<ServoComputedValues>()
 });
 
 /// Performs the CSS cascade, computing new styles for an element from its parent style and
diff --git a/ports/geckolib/bindings.rs b/ports/geckolib/bindings.rs
index 5dcb7be670a..2c92184f8e7 100644
--- a/ports/geckolib/bindings.rs
+++ b/ports/geckolib/bindings.rs
@@ -11,6 +11,33 @@ pub enum ServoNodeData { }
 pub enum ServoComputedValues { }
 pub enum RawServoStyleSheet { }
 pub enum RawServoStyleSet { }
+
+// Temporary manual hack. This will be fixed soon in bindgen.
+use gecko_style_structs::nsStyleFont;
+use gecko_style_structs::nsStyleColor;
+use gecko_style_structs::nsStyleList;
+use gecko_style_structs::nsStyleText;
+use gecko_style_structs::nsStyleVisibility;
+use gecko_style_structs::nsStyleQuotes;
+use gecko_style_structs::nsStyleUserInterface;
+use gecko_style_structs::nsStyleTableBorder;
+use gecko_style_structs::nsStyleSVG;
+use gecko_style_structs::nsStyleVariables;
+use gecko_style_structs::nsStyleBackground;
+use gecko_style_structs::nsStylePosition;
+use gecko_style_structs::nsStyleTextReset;
+use gecko_style_structs::nsStyleDisplay;
+use gecko_style_structs::nsStyleContent;
+use gecko_style_structs::nsStyleUIReset;
+use gecko_style_structs::nsStyleTable;
+use gecko_style_structs::nsStyleMargin;
+use gecko_style_structs::nsStylePadding;
+use gecko_style_structs::nsStyleBorder;
+use gecko_style_structs::nsStyleOutline;
+use gecko_style_structs::nsStyleXUL;
+use gecko_style_structs::nsStyleSVGReset;
+use gecko_style_structs::nsStyleColumn;
+
 extern "C" {
     pub fn Gecko_ChildrenCount(node: *mut RawGeckoNode) -> u32;
     pub fn Gecko_NodeIsElement(node: *mut RawGeckoNode) -> bool;
@@ -56,13 +83,6 @@ extern "C" {
     pub fn Servo_StyleSheetHasRules(sheet: *mut RawServoStyleSheet) -> bool;
     pub fn Servo_InitStyleSet() -> *mut RawServoStyleSet;
     pub fn Servo_DropStyleSet(set: *mut RawServoStyleSet);
-    pub fn Gecko_GetAttrAsUTF8(element: *mut RawGeckoElement, ns: *const u8,
-                               name: *const u8, length: *mut u32)
-     -> *const ::std::os::raw::c_char;
-    pub fn Gecko_LocalName(element: *mut RawGeckoElement, length: *mut u32)
-     -> *const u16;
-    pub fn Gecko_Namespace(element: *mut RawGeckoElement, length: *mut u32)
-     -> *const u16;
     pub fn Servo_GetComputedValues(element: *mut RawGeckoElement)
      -> *mut ServoComputedValues;
     pub fn Servo_GetComputedValuesForAnonymousBox(parentStyleOrNull:
@@ -71,6 +91,118 @@ extern "C" {
      -> *mut ServoComputedValues;
     pub fn Servo_AddRefComputedValues(arg1: *mut ServoComputedValues);
     pub fn Servo_ReleaseComputedValues(arg1: *mut ServoComputedValues);
+    pub fn Gecko_GetAttrAsUTF8(element: *mut RawGeckoElement, ns: *const u8,
+                               name: *const u8, length: *mut u32)
+     -> *const ::std::os::raw::c_char;
+    pub fn Gecko_LocalName(element: *mut RawGeckoElement, length: *mut u32)
+     -> *const u16;
+    pub fn Gecko_Namespace(element: *mut RawGeckoElement, length: *mut u32)
+     -> *const u16;
     pub fn Servo_RestyleDocument(doc: *mut RawGeckoDocument,
                                  set: *mut RawServoStyleSet);
+    pub fn Gecko_Construct_nsStyleFont(ptr: *mut nsStyleFont);
+    pub fn Gecko_CopyConstruct_nsStyleFont(ptr: *mut nsStyleFont,
+                                           other: *const nsStyleFont);
+    pub fn Gecko_Destroy_nsStyleFont(ptr: *mut nsStyleFont);
+    pub fn Gecko_Construct_nsStyleColor(ptr: *mut nsStyleColor);
+    pub fn Gecko_CopyConstruct_nsStyleColor(ptr: *mut nsStyleColor,
+                                            other: *const nsStyleColor);
+    pub fn Gecko_Destroy_nsStyleColor(ptr: *mut nsStyleColor);
+    pub fn Gecko_Construct_nsStyleList(ptr: *mut nsStyleList);
+    pub fn Gecko_CopyConstruct_nsStyleList(ptr: *mut nsStyleList,
+                                           other: *const nsStyleList);
+    pub fn Gecko_Destroy_nsStyleList(ptr: *mut nsStyleList);
+    pub fn Gecko_Construct_nsStyleText(ptr: *mut nsStyleText);
+    pub fn Gecko_CopyConstruct_nsStyleText(ptr: *mut nsStyleText,
+                                           other: *const nsStyleText);
+    pub fn Gecko_Destroy_nsStyleText(ptr: *mut nsStyleText);
+    pub fn Gecko_Construct_nsStyleVisibility(ptr: *mut nsStyleVisibility);
+    pub fn Gecko_CopyConstruct_nsStyleVisibility(ptr: *mut nsStyleVisibility,
+                                                 other:
+                                                     *const nsStyleVisibility);
+    pub fn Gecko_Destroy_nsStyleVisibility(ptr: *mut nsStyleVisibility);
+    pub fn Gecko_Construct_nsStyleQuotes(ptr: *mut nsStyleQuotes);
+    pub fn Gecko_CopyConstruct_nsStyleQuotes(ptr: *mut nsStyleQuotes,
+                                             other: *const nsStyleQuotes);
+    pub fn Gecko_Destroy_nsStyleQuotes(ptr: *mut nsStyleQuotes);
+    pub fn Gecko_Construct_nsStyleUserInterface(ptr:
+                                                    *mut nsStyleUserInterface);
+    pub fn Gecko_CopyConstruct_nsStyleUserInterface(ptr:
+                                                        *mut nsStyleUserInterface,
+                                                    other:
+                                                        *const nsStyleUserInterface);
+    pub fn Gecko_Destroy_nsStyleUserInterface(ptr: *mut nsStyleUserInterface);
+    pub fn Gecko_Construct_nsStyleTableBorder(ptr: *mut nsStyleTableBorder);
+    pub fn Gecko_CopyConstruct_nsStyleTableBorder(ptr:
+                                                      *mut nsStyleTableBorder,
+                                                  other:
+                                                      *const nsStyleTableBorder);
+    pub fn Gecko_Destroy_nsStyleTableBorder(ptr: *mut nsStyleTableBorder);
+    pub fn Gecko_Construct_nsStyleSVG(ptr: *mut nsStyleSVG);
+    pub fn Gecko_CopyConstruct_nsStyleSVG(ptr: *mut nsStyleSVG,
+                                          other: *const nsStyleSVG);
+    pub fn Gecko_Destroy_nsStyleSVG(ptr: *mut nsStyleSVG);
+    pub fn Gecko_Construct_nsStyleVariables(ptr: *mut nsStyleVariables);
+    pub fn Gecko_CopyConstruct_nsStyleVariables(ptr: *mut nsStyleVariables,
+                                                other:
+                                                    *const nsStyleVariables);
+    pub fn Gecko_Destroy_nsStyleVariables(ptr: *mut nsStyleVariables);
+    pub fn Gecko_Construct_nsStyleBackground(ptr: *mut nsStyleBackground);
+    pub fn Gecko_CopyConstruct_nsStyleBackground(ptr: *mut nsStyleBackground,
+                                                 other:
+                                                     *const nsStyleBackground);
+    pub fn Gecko_Destroy_nsStyleBackground(ptr: *mut nsStyleBackground);
+    pub fn Gecko_Construct_nsStylePosition(ptr: *mut nsStylePosition);
+    pub fn Gecko_CopyConstruct_nsStylePosition(ptr: *mut nsStylePosition,
+                                               other: *const nsStylePosition);
+    pub fn Gecko_Destroy_nsStylePosition(ptr: *mut nsStylePosition);
+    pub fn Gecko_Construct_nsStyleTextReset(ptr: *mut nsStyleTextReset);
+    pub fn Gecko_CopyConstruct_nsStyleTextReset(ptr: *mut nsStyleTextReset,
+                                                other:
+                                                    *const nsStyleTextReset);
+    pub fn Gecko_Destroy_nsStyleTextReset(ptr: *mut nsStyleTextReset);
+    pub fn Gecko_Construct_nsStyleDisplay(ptr: *mut nsStyleDisplay);
+    pub fn Gecko_CopyConstruct_nsStyleDisplay(ptr: *mut nsStyleDisplay,
+                                              other: *const nsStyleDisplay);
+    pub fn Gecko_Destroy_nsStyleDisplay(ptr: *mut nsStyleDisplay);
+    pub fn Gecko_Construct_nsStyleContent(ptr: *mut nsStyleContent);
+    pub fn Gecko_CopyConstruct_nsStyleContent(ptr: *mut nsStyleContent,
+                                              other: *const nsStyleContent);
+    pub fn Gecko_Destroy_nsStyleContent(ptr: *mut nsStyleContent);
+    pub fn Gecko_Construct_nsStyleUIReset(ptr: *mut nsStyleUIReset);
+    pub fn Gecko_CopyConstruct_nsStyleUIReset(ptr: *mut nsStyleUIReset,
+                                              other: *const nsStyleUIReset);
+    pub fn Gecko_Destroy_nsStyleUIReset(ptr: *mut nsStyleUIReset);
+    pub fn Gecko_Construct_nsStyleTable(ptr: *mut nsStyleTable);
+    pub fn Gecko_CopyConstruct_nsStyleTable(ptr: *mut nsStyleTable,
+                                            other: *const nsStyleTable);
+    pub fn Gecko_Destroy_nsStyleTable(ptr: *mut nsStyleTable);
+    pub fn Gecko_Construct_nsStyleMargin(ptr: *mut nsStyleMargin);
+    pub fn Gecko_CopyConstruct_nsStyleMargin(ptr: *mut nsStyleMargin,
+                                             other: *const nsStyleMargin);
+    pub fn Gecko_Destroy_nsStyleMargin(ptr: *mut nsStyleMargin);
+    pub fn Gecko_Construct_nsStylePadding(ptr: *mut nsStylePadding);
+    pub fn Gecko_CopyConstruct_nsStylePadding(ptr: *mut nsStylePadding,
+                                              other: *const nsStylePadding);
+    pub fn Gecko_Destroy_nsStylePadding(ptr: *mut nsStylePadding);
+    pub fn Gecko_Construct_nsStyleBorder(ptr: *mut nsStyleBorder);
+    pub fn Gecko_CopyConstruct_nsStyleBorder(ptr: *mut nsStyleBorder,
+                                             other: *const nsStyleBorder);
+    pub fn Gecko_Destroy_nsStyleBorder(ptr: *mut nsStyleBorder);
+    pub fn Gecko_Construct_nsStyleOutline(ptr: *mut nsStyleOutline);
+    pub fn Gecko_CopyConstruct_nsStyleOutline(ptr: *mut nsStyleOutline,
+                                              other: *const nsStyleOutline);
+    pub fn Gecko_Destroy_nsStyleOutline(ptr: *mut nsStyleOutline);
+    pub fn Gecko_Construct_nsStyleXUL(ptr: *mut nsStyleXUL);
+    pub fn Gecko_CopyConstruct_nsStyleXUL(ptr: *mut nsStyleXUL,
+                                          other: *const nsStyleXUL);
+    pub fn Gecko_Destroy_nsStyleXUL(ptr: *mut nsStyleXUL);
+    pub fn Gecko_Construct_nsStyleSVGReset(ptr: *mut nsStyleSVGReset);
+    pub fn Gecko_CopyConstruct_nsStyleSVGReset(ptr: *mut nsStyleSVGReset,
+                                               other: *const nsStyleSVGReset);
+    pub fn Gecko_Destroy_nsStyleSVGReset(ptr: *mut nsStyleSVGReset);
+    pub fn Gecko_Construct_nsStyleColumn(ptr: *mut nsStyleColumn);
+    pub fn Gecko_CopyConstruct_nsStyleColumn(ptr: *mut nsStyleColumn,
+                                             other: *const nsStyleColumn);
+    pub fn Gecko_Destroy_nsStyleColumn(ptr: *mut nsStyleColumn);
 }
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 72fbf90e4ff..1bb4797e92e 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -22,6 +22,7 @@ use style::context::{ReflowGoal, StylistWrapper};
 use style::dom::{TDocument, TElement, TNode};
 use style::error_reporting::StdoutErrorReporter;
 use style::parallel;
+use style::properties::ComputedValues;
 use style::stylesheets::Origin;
 use traversal::RecalcStyleOnly;
 use url::Url;
@@ -45,6 +46,11 @@ pub extern "C" fn Servo_RestyleDocument(doc: *mut RawGeckoDocument, raw_data: *m
     };
     let data = unsafe { &mut *(raw_data as *mut PerDocumentStyleData) };
 
+    // Force the creation of our lazily-constructed initial computed values on
+    // the main thread, since it's not safe to call elsewhere. This should move
+    // into a runtime-wide init hook at some point.
+    GeckoComputedValues::initial_values();
+
     let _needs_dirtying = data.stylist.update(&data.stylesheets, data.stylesheets_changed);
     data.stylesheets_changed = false;
 
diff --git a/ports/geckolib/properties.mako.rs b/ports/geckolib/properties.mako.rs
index 053e730281c..94407b18c8f 100644
--- a/ports/geckolib/properties.mako.rs
+++ b/ports/geckolib/properties.mako.rs
@@ -6,6 +6,9 @@ use app_units::Au;
 % for style_struct in STYLE_STRUCTS:
 %if style_struct.gecko_name:
 use gecko_style_structs::${style_struct.gecko_name};
+use bindings::Gecko_Construct_${style_struct.gecko_name};
+use bindings::Gecko_CopyConstruct_${style_struct.gecko_name};
+use bindings::Gecko_Destroy_${style_struct.gecko_name};
 % endif
 % endfor
 use heapsize::HeapSizeOf;
@@ -16,6 +19,7 @@ use style::custom_properties::ComputedValuesMap;
 use style::logical_geometry::WritingMode;
 use style::properties::{CascadePropertyFn, ServoComputedValues, ComputedValues};
 use style::properties::longhands;
+use style::properties::make_cascade_vec;
 use style::properties::style_struct_traits::*;
 
 #[derive(Clone)]
@@ -58,10 +62,10 @@ impl ComputedValues for GeckoComputedValues {
         }
     }
 
-    fn initial_values() -> &'static Self { unimplemented!() }
+    fn initial_values() -> &'static Self { &*INITIAL_GECKO_VALUES }
 
-    fn do_cascade_property<F: FnOnce(&Vec<Option<CascadePropertyFn<Self>>>)>(_: F) {
-        unimplemented!()
+    fn do_cascade_property<F: FnOnce(&Vec<Option<CascadePropertyFn<Self>>>)>(f: F) {
+        CASCADE_PROPERTY.with(|x| f(x));
     }
 
     % for style_struct in STYLE_STRUCTS:
@@ -104,8 +108,11 @@ impl Gecko${style_struct.name} {
     #[allow(dead_code, unused_variables)]
     fn initial() -> Self {
 % if style_struct.gecko_name:
-        let result = Gecko${style_struct.name} { gecko: unsafe { zeroed() } };
-        panic!("Need to invoke Gecko placement new");
+        let mut result = Gecko${style_struct.name} { gecko: unsafe { zeroed() } };
+        unsafe {
+            Gecko_Construct_${style_struct.gecko_name}(&mut result.gecko);
+        }
+        result
 % else:
         Gecko${style_struct.name}
 % endif
@@ -114,12 +121,18 @@ impl Gecko${style_struct.name} {
 %if style_struct.gecko_name:
 impl Drop for Gecko${style_struct.name} {
     fn drop(&mut self) {
-        panic!("Need to invoke Gecko destructor");
+        unsafe {
+            Gecko_Destroy_${style_struct.gecko_name}(&mut self.gecko);
+        }
     }
 }
 impl Clone for ${style_struct.gecko_name} {
     fn clone(&self) -> Self {
-        panic!("Need to invoke Gecko copy constructor");
+        unsafe {
+            let mut result: Self = zeroed();
+            Gecko_CopyConstruct_${style_struct.gecko_name}(&mut result, self);
+            result
+        }
     }
 }
 unsafe impl Send for ${style_struct.gecko_name} {}
@@ -205,3 +218,21 @@ ${impl_style_struct(style_struct)}
 <%self:raw_impl_trait style_struct="${style_struct}"></%self:raw_impl_trait>
 % endif
 % endfor
+
+lazy_static! {
+    pub static ref INITIAL_GECKO_VALUES: GeckoComputedValues = GeckoComputedValues {
+        % for style_struct in STYLE_STRUCTS:
+           ${style_struct.ident}: Arc::new(Gecko${style_struct.name}::initial()),
+        % endfor
+        custom_properties: None,
+        shareable: true,
+        writing_mode: WritingMode::empty(),
+        root_font_size: longhands::font_size::get_initial_value(),
+    };
+}
+
+// This is a thread-local rather than a lazy static to avoid atomic operations when cascading
+// properties.
+thread_local!(static CASCADE_PROPERTY: Vec<Option<CascadePropertyFn<GeckoComputedValues>>> = {
+    make_cascade_vec::<GeckoComputedValues>()
+});
diff --git a/ports/geckolib/tools/regen_bindings.sh b/ports/geckolib/tools/regen_bindings.sh
index 77ee56ee5bf..02291c07084 100755
--- a/ports/geckolib/tools/regen_bindings.sh
+++ b/ports/geckolib/tools/regen_bindings.sh
@@ -38,3 +38,4 @@ fi
   -no-type-renaming                                \
   "$DIST_INCLUDE/mozilla/ServoBindings.h"          \
   -match "ServoBindings.h"                         \
+  -match "nsStyleStructList.h"                     \