Provide an interface to the engine for the script task

src/components/main/engine.rs

@@ -4,29 +4,21 @@
 
 use compositing::CompositorTask;
 use layout::layout_task;
-use util::task::spawn_listener;
 
 use core::cell::Cell;
-use core::comm::{Chan, Port, SharedChan};
+use core::comm::{Port, SharedChan};
 use gfx::opts::Opts;
 use gfx::render_task::RenderTask;
 use gfx::render_task;
+use script::engine_interface::{EngineTask, ExitMsg, LoadUrlMsg, Msg};
 use script::layout_interface::LayoutTask;
 use script::layout_interface;
 use script::script_task::{ExecuteMsg, LoadMsg, ScriptMsg, ScriptTask};
 use script::script_task;
 use servo_net::image_cache_task::{ImageCacheTask, ImageCacheTaskClient};
 use servo_net::resource_task::ResourceTask;
 use servo_net::resource_task;
-use servo_util::time::{profiler_force_print, ProfilerChan, ProfilerPort, ProfilerTask};
-use std::net::url::Url;
-
-pub type EngineTask = Chan<Msg>;
-
-pub enum Msg {
-    LoadUrlMsg(Url),
-    ExitMsg(Chan<()>),
-}
+use servo_util::time::{ProfilerChan, ProfilerPort, ProfilerTask, ForcePrintMsg};
 
 pub struct Engine {
     request_port: Port<Msg>,
@@ -41,7 +33,7 @@ pub struct Engine {
 
 impl Drop for Engine {
     fn finalize(&self) {
-        profiler_force_print(self.profiler_task.chan.clone()); 
+        self.profiler_task.chan.send(ForcePrintMsg);
     }
 }
 
@@ -56,10 +48,13 @@ impl Engine {
                  profiler_chan: ProfilerChan)
                  -> EngineTask {
         let (script_port, script_chan) = (Cell(script_port), Cell(script_chan));
+        let (request_port, request_chan) = comm::stream();
+        let (request_port, request_chan) = (Cell(request_port), SharedChan::new(request_chan));
+        let request_chan_clone = request_chan.clone();
         let profiler_port = Cell(profiler_port);
         let opts = Cell(copy *opts);
 
-        do spawn_listener::<Msg> |request| {
+        do task::spawn {
             let render_task = RenderTask::new(compositor.clone(),
                                               opts.with_ref(|o| copy *o),
                                               profiler_chan.clone());
@@ -77,22 +72,24 @@ impl Engine {
 
             let script_task = ScriptTask::new(script_port.take(),
                                               script_chan.take(),
+                                              request_chan_clone.clone(),
                                               layout_task.clone(),
                                               resource_task.clone(),
                                               image_cache_task.clone());
 
 
             Engine {
-                request_port: request,
+                request_port: request_port.take(),
                 compositor: compositor.clone(),
                 render_task: render_task,
                 resource_task: resource_task.clone(),
                 image_cache_task: image_cache_task.clone(),
                 layout_task: layout_task,
                 script_task: script_task,
                 profiler_task: profiler_task,
-            }.run()
+            }.run();
         }
+        request_chan.clone()
     }
 
     fn run(&self) {

src/components/main/servo.rc

@@ -34,7 +34,8 @@ extern mod core_graphics;
 extern mod core_text;
 
 use compositing::CompositorTask;
-use engine::{Engine, LoadUrlMsg};
+use engine::Engine;
+use script::engine_interface::{ExitMsg, LoadUrlMsg};
 
 use core::comm::SharedChan;
 use gfx::opts;
@@ -121,7 +122,7 @@ fn run(opts: &Opts) {
     // Shut the engine down.
     debug!("master: Shut down");
     let (exit_response_from_engine, exit_chan) = comm::stream();
-    engine_task.send(engine::ExitMsg(exit_chan));
+    engine_task.send(ExitMsg(exit_chan));
     exit_response_from_engine.recv();
 }
 

src/components/net/util.rs

@@ -5,11 +5,11 @@
 use core::comm::{Chan, Port};
 
 pub fn spawn_listener<A: Owned>(f: ~fn(Port<A>)) -> Chan<A> {
-    let (setup_po, setup_ch) = comm::stream();
+    let (setup_port, setup_chan) = comm::stream();
     do task::spawn {
-        let (po, ch) = comm::stream();
-        setup_ch.send(ch);
-        f(po);
+        let (port, chan) = comm::stream();
+        setup_chan.send(chan);
+        f(port);
     }
-    setup_po.recv()
+    setup_port.recv()
 }

src/components/script/engine_interface.rs

@@ -0,0 +1,17 @@
+/* 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/. */
+
+//! The high-level interface from script to engine. Using this abstract interface helps reduce
+/// coupling between these two components
+
+use core::comm::{Chan, SharedChan};
+use std::net::url::Url;
+
+pub type EngineTask = SharedChan<Msg>;
+
+pub enum Msg {
+    LoadUrlMsg(Url),
+    ExitMsg(Chan<()>),
+}
+

src/components/script/script.rc

@@ -65,5 +65,6 @@ pub mod html {
 }
 
 pub mod layout_interface;
+pub mod engine_interface;
 pub mod script_task;
 

src/components/script/script_task.rs

@@ -16,6 +16,7 @@ use layout_interface::{HitTestResponse, LayoutQuery, LayoutResponse, LayoutTask}
 use layout_interface::{MatchSelectorsDocumentDamage, QueryMsg, Reflow, ReflowDocumentDamage};
 use layout_interface::{ReflowForDisplay, ReflowForScriptQuery, ReflowGoal, ReflowMsg};
 use layout_interface;
+use engine_interface::{EngineTask, LoadUrlMsg};
 
 use core::cast::transmute;
 use core::cell::Cell;
@@ -65,6 +66,7 @@ impl ScriptTask {
     /// Creates a new script task.
     pub fn new(script_port: Port<ScriptMsg>,
                script_chan: SharedChan<ScriptMsg>,
+               engine_task: EngineTask,
                layout_task: LayoutTask,
                resource_task: ResourceTask,
                image_cache_task: ImageCacheTask)
@@ -78,6 +80,7 @@ impl ScriptTask {
             let script_context = ScriptContext::new(layout_task.clone(),
                                                     script_port.take(),
                                                     script_chan_copy.clone(),
+                                                    engine_task.clone(),
                                                     resource_task.clone(),
                                                     image_cache_task.clone());
             script_context.start();
@@ -117,6 +120,9 @@ pub struct ScriptContext {
     /// messages.
     script_chan: SharedChan<ScriptMsg>,
 
+    /// For communicating load url messages to the engine
+    engine_task: EngineTask,
+
     /// The JavaScript runtime.
     js_runtime: js::rust::rt,
     /// The JavaScript context.
@@ -168,6 +174,7 @@ impl ScriptContext {
     pub fn new(layout_task: LayoutTask,
                script_port: Port<ScriptMsg>,
                script_chan: SharedChan<ScriptMsg>,
+               engine_task: EngineTask,
                resource_task: ResourceTask,
                img_cache_task: ImageCacheTask)
                -> @mut ScriptContext {
@@ -191,6 +198,8 @@ impl ScriptContext {
             script_port: script_port,
             script_chan: script_chan,
 
+            engine_task: engine_task,
+
             js_runtime: js_runtime,
             js_context: js_context,
             js_compartment: compartment,
@@ -552,7 +561,7 @@ impl ScriptContext {
                 debug!("clicked on link to %?", attr.value); 
                 let url = from_str(attr.value);
                 match url {
-                    Ok(url) => self.script_chan.send(LoadMsg(url)),
+                    Ok(url) => self.engine_task.send(LoadUrlMsg(url)),
                     Err(msg) => debug!(msg)
                 };
                 break;

src/components/util/time.rs

@@ -8,6 +8,9 @@ use core::cell::Cell;
 use core::comm::{Port, SharedChan};
 use std::sort::tim_sort;
 
+pub type ProfilerChan = SharedChan<ProfilerMsg>;
+pub type ProfilerPort = Port<ProfilerMsg>;
+
 #[deriving(Eq)]
 pub enum ProfilerCategory {
     CompositingCategory,
@@ -26,6 +29,29 @@ pub enum ProfilerCategory {
     // hackish but helps prevent errors when adding new categories
     NUM_BUCKETS,
 }
+// FIXME(#5873) this should be initialized by a NUM_BUCKETS cast,
+static BUCKETS: uint = 13;
+
+pub enum ProfilerMsg {
+    // Normal message used for reporting time
+    TimeMsg(ProfilerCategory, f64),
+    // Message used to force print the profiling metrics
+    ForcePrintMsg,
+}
+
+// front-end representation of the profiler used to communicate with the profiler context
+pub struct ProfilerTask {
+    chan: ProfilerChan,
+}
+
+// back end of the profiler that handles data aggregation and performance metrics
+pub struct ProfilerContext {
+    port: ProfilerPort,
+    buckets: ~[(ProfilerCategory, ~[f64])],
+    verbose: bool,
+    period: f64,
+    last_print: f64,
+}
 
 impl ProfilerCategory {
 
@@ -76,20 +102,6 @@ impl ProfilerCategory {
         fmt!("%s%?", padding, self)
     }
 }
-// FIXME(#5873) this should be initialized by a NUM_BUCKETS cast,
-static BUCKETS: uint = 13;
-
-pub enum ProfilerMsg {
-    // Normal message used for reporting time
-    TimeMsg(ProfilerCategory, f64),
-    // Message used to force print the profiling metrics
-    ForcePrintMsg,
-}
-pub type ProfilerChan = SharedChan<ProfilerMsg>;
-pub type ProfilerPort = Port<ProfilerMsg>;
-pub struct ProfilerTask {
-    chan: ProfilerChan,
-}
 
 impl ProfilerTask {
     pub fn new(profiler_port: ProfilerPort,
@@ -109,14 +121,6 @@ impl ProfilerTask {
     }
 }
 
-pub struct ProfilerContext {
-    port: ProfilerPort,
-    buckets: ~[(ProfilerCategory, ~[f64])],
-    verbose: bool,
-    period: f64,
-    mut last_print: f64,
-}
-
 impl ProfilerContext {
     pub fn new(port: ProfilerPort, period: Option<f64>) -> ProfilerContext {
         let (verbose, period) = match period {
@@ -197,11 +201,6 @@ pub fn profile<T>(category: ProfilerCategory,
     return val;
 }
 
-
-pub fn profiler_force_print(profiler_chan: ProfilerChan) {
-    profiler_chan.send(ForcePrintMsg);
-}
-
 pub fn time<T>(msg: &str, callback: &fn() -> T) -> T{
     let start_time = precise_time_ns();
     let val = callback();