layout: Make the `LayoutControlChan` use IPC.

components/compositing/constellation.rs

@@ -19,6 +19,7 @@ use euclid::rect::{Rect, TypedRect};
 use euclid::size::Size2D;
 use euclid::scale_factor::ScaleFactor;
 use gfx::font_cache_task::FontCacheTask;
+use ipc_channel::ipc;
 use layout_traits::{LayoutControlChan, LayoutControlMsg, LayoutTaskFactory};
 use libc;
 use msg::compositor_msg::{Epoch, LayerId};
@@ -1128,7 +1129,7 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
                             // epoch matches what the compositor has drawn. If they match
                             // (and script is idle) then this pipeline won't change again
                             // and can be considered stable.
-                            let (sender, receiver) = channel();
+                            let (sender, receiver) = ipc::channel().unwrap();
                             let LayoutControlChan(ref layout_chan) = pipeline.layout_chan;
                             layout_chan.send(LayoutControlMsg::GetCurrentEpoch(sender)).unwrap();
                             let layout_task_epoch = receiver.recv().unwrap();

components/compositing/pipeline.rs

@@ -85,7 +85,7 @@ impl Pipeline {
         let (paint_port, paint_chan) = PaintChan::new();
         let (paint_shutdown_chan, paint_shutdown_port) = channel();
         let (layout_shutdown_chan, layout_shutdown_port) = channel();
-        let (pipeline_chan, pipeline_port) = channel();
+        let (pipeline_chan, pipeline_port) = ipc::channel().unwrap();
 
         let failure = Failure {
             pipeline_id: id,

components/layout/Cargo.toml

@@ -55,6 +55,9 @@ git = "https://github.com/servo/rust-selectors"
 [dependencies.clock_ticks]
 git = "https://github.com/tomaka/clock_ticks"
 
+[dependencies.ipc-channel]
+git = "https://github.com/pcwalton/ipc-channel"
+
 [dependencies]
 log = "*"
 encoding = "0.2"

components/layout/layout_task.rs

@@ -39,6 +39,7 @@ use gfx::display_list::StackingContext;
 use gfx::font_cache_task::FontCacheTask;
 use gfx::paint_task::Msg as PaintMsg;
 use gfx::paint_task::{PaintChan, PaintLayer};
+use ipc_channel::ipc::IpcReceiver;
 use layout_traits::{LayoutControlMsg, LayoutTaskFactory};
 use log;
 use msg::compositor_msg::{Epoch, ScrollPolicy, LayerId};
@@ -65,6 +66,7 @@ use std::mem::transmute;
 use std::ops::{Deref, DerefMut};
 use std::sync::mpsc::{channel, Sender, Receiver, Select};
 use std::sync::{Arc, Mutex, MutexGuard};
+use std::thread;
 use style::computed_values::{filter, mix_blend_mode};
 use style::media_queries::{MediaType, MediaQueryList, Device};
 use style::selector_matching::Stylist;
@@ -155,7 +157,7 @@ pub struct LayoutTask {
     /// The port on which we receive messages from the script task.
     pub port: Receiver<Msg>,
 
-    /// The port on which we receive messages from the constellation
+    /// The port on which we receive messages from the constellation.
     pub pipeline_port: Receiver<LayoutControlMsg>,
 
     /// The port on which we receive messages from the image cache
@@ -213,7 +215,7 @@ impl LayoutTaskFactory for LayoutTask {
               url: Url,
               is_iframe: bool,
               chan: OpaqueScriptLayoutChannel,
-              pipeline_port: Receiver<LayoutControlMsg>,
+              pipeline_port: IpcReceiver<LayoutControlMsg>,
               constellation_chan: ConstellationChan,
               failure_msg: Failure,
               script_chan: ScriptControlChan,
@@ -284,7 +286,7 @@ impl LayoutTask {
            is_iframe: bool,
            port: Receiver<Msg>,
            chan: LayoutChan,
-           pipeline_port: Receiver<LayoutControlMsg>,
+           pipeline_port: IpcReceiver<LayoutControlMsg>,
            constellation_chan: ConstellationChan,
            script_chan: ScriptControlChan,
            paint_chan: PaintChan,
@@ -314,12 +316,20 @@ impl LayoutTask {
         let (image_cache_sender, image_cache_receiver) = channel();
         let (canvas_layers_sender, canvas_layers_receiver) = channel();
 
+        // Start a thread to proxy IPC messages from the layout thread to us.
+        let (pipeline_sender, pipeline_receiver) = channel();
+        thread::spawn(move || {
+            while let Ok(message) = pipeline_port.recv() {
+                pipeline_sender.send(message).unwrap()
+            }
+        });
+
         LayoutTask {
             id: id,
             url: url,
             is_iframe: is_iframe,
             port: port,
-            pipeline_port: pipeline_port,
+            pipeline_port: pipeline_receiver,
             chan: chan,
             script_chan: script_chan,
             constellation_chan: constellation_chan.clone(),

components/layout/lib.rs

@@ -46,6 +46,7 @@ extern crate fnv;
 extern crate euclid;
 extern crate gfx;
 extern crate gfx_traits;
+extern crate ipc_channel;
 extern crate layout_traits;
 extern crate libc;
 extern crate msg;

components/layout_traits/Cargo.toml

@@ -25,6 +25,12 @@ path = "../profile_traits"
 [dependencies.util]
 path = "../util"
 
+[dependencies.ipc-channel]
+git = "https://github.com/pcwalton/ipc-channel"
+
 [dependencies]
 url = "0.2.35"
 euclid = "0.1"
+serde = "*"
+serde_macros = "*"
+

components/layout_traits/lib.rs

@@ -2,12 +2,17 @@
  * 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/. */
 
+#![feature(custom_derive, plugin)]
+#![plugin(serde_macros)]
+
 extern crate euclid;
 extern crate gfx;
+extern crate ipc_channel;
 extern crate script_traits;
 extern crate msg;
 extern crate profile_traits;
 extern crate net_traits;
+extern crate serde;
 extern crate url;
 extern crate util;
 
@@ -19,27 +24,29 @@ extern crate util;
 use euclid::rect::Rect;
 use gfx::font_cache_task::FontCacheTask;
 use gfx::paint_task::PaintChan;
+use ipc_channel::ipc::{IpcReceiver, IpcSender};
 use msg::compositor_msg::{Epoch, LayerId};
 use msg::constellation_msg::{ConstellationChan, Failure, PipelineId, PipelineExitType};
 use profile_traits::mem;
 use profile_traits::time;
 use net_traits::image_cache_task::ImageCacheTask;
 use script_traits::{ScriptControlChan, OpaqueScriptLayoutChannel};
-use std::sync::mpsc::{Sender, Receiver};
+use std::sync::mpsc::Sender;
 use util::geometry::Au;
 use url::Url;
 
 /// Messages sent to the layout task from the constellation and/or compositor.
+#[derive(Deserialize, Serialize)]
 pub enum LayoutControlMsg {
     ExitNow(PipelineExitType),
-    GetCurrentEpoch(Sender<Epoch>),
+    GetCurrentEpoch(IpcSender<Epoch>),
     TickAnimations,
     SetVisibleRects(Vec<(LayerId, Rect<Au>)>),
 }
 
 /// A channel wrapper for constellation messages
-#[derive(Clone)]
-pub struct LayoutControlChan(pub Sender<LayoutControlMsg>);
+#[derive(Clone, Deserialize, Serialize)]
+pub struct LayoutControlChan(pub IpcSender<LayoutControlMsg>);
 
 // A static method creating a layout task
 // Here to remove the compositor -> layout dependency
@@ -50,7 +57,7 @@ pub trait LayoutTaskFactory {
               url: Url,
               is_iframe: bool,
               chan: OpaqueScriptLayoutChannel,
-              pipeline_port: Receiver<LayoutControlMsg>,
+              pipeline_port: IpcReceiver<LayoutControlMsg>,
               constellation_chan: ConstellationChan,
               failure_msg: Failure,
               script_chan: ScriptControlChan,

components/msg/compositor_msg.rs

@@ -16,7 +16,7 @@ use std::fmt;
 use constellation_msg::PipelineId;
 
 /// A newtype struct for denoting the age of messages; prevents race conditions.
-#[derive(PartialEq, Eq, Debug, Copy, Clone, PartialOrd, Ord)]
+#[derive(PartialEq, Eq, Debug, Copy, Clone, PartialOrd, Ord, Deserialize, Serialize)]
 pub struct Epoch(pub u32);
 
 impl Epoch {

components/msg/constellation_msg.rs

@@ -377,7 +377,7 @@ pub struct SubpageId(pub u32);
 
 // The type of pipeline exit. During complete shutdowns, pipelines do not have to
 // release resources automatically released on process termination.
-#[derive(Copy, Clone, Debug)]
+#[derive(Copy, Clone, Debug, Deserialize, Serialize)]
 pub enum PipelineExitType {
     PipelineOnly,
     Complete,

components/script/Cargo.toml

@@ -55,6 +55,9 @@ features = ["query_encoding"]
 [dependencies.offscreen_gl_context]
 git = "https://github.com/ecoal95/rust-offscreen-rendering-context"
 
+[dependencies.ipc-channel]
+git = "https://github.com/pcwalton/ipc-channel"
+
 [dependencies]
 log = "*"
 encoding = "0.2"

components/script/layout_interface.rs

@@ -10,6 +10,7 @@ use dom::node::LayoutData;
 
 use euclid::point::Point2D;
 use euclid::rect::Rect;
+use ipc_channel::ipc::IpcSender;
 use libc::uintptr_t;
 use msg::compositor_msg::LayerId;
 use msg::constellation_msg::{PipelineExitType, WindowSizeData};
@@ -71,7 +72,7 @@ pub enum Msg {
     ExitNow(PipelineExitType),
 
     /// Get the last epoch counter for this layout task.
-    GetCurrentEpoch(Sender<Epoch>)
+    GetCurrentEpoch(IpcSender<Epoch>)
 }
 
 /// Synchronous messages that script can send to layout.

components/script/lib.rs

@@ -44,6 +44,7 @@ extern crate html5ever;
 extern crate encoding;
 extern crate fnv;
 extern crate hyper;
+extern crate ipc_channel;
 extern crate js;
 extern crate libc;
 extern crate msg;