Auto merge of #8523 - Wafflespeanut:redirects, r=jdm

Listen for cancellation message during loads and redirects...

fixes #8495

<!-- Reviewable:start -->
[<img src="https://reviewable.io/review_button.png" height=40 alt="Review on Reviewable"/>](https://reviewable.io/reviews/servo/servo/8523)
<!-- Reviewable:end -->

components/net/http_loader.rs

@@ -115,7 +115,10 @@ fn load_for_consumer(load_data: LoadData,
     let factory = NetworkHttpRequestFactory {
         connector: connector,
     };
-    match load::<WrappedHttpRequest>(load_data, hsts_list, cookie_jar, devtools_chan, &factory, user_agent) {
+    match load::<WrappedHttpRequest>(load_data, hsts_list,
+                                     cookie_jar, devtools_chan,
+                                     &factory, user_agent,
+                                     &cancel_listener) {
         Err(LoadError::UnsupportedScheme(url)) => {
             let s = format!("{} request, but we don't support that scheme", &*url.scheme);
             send_error(url, s, start_chan)
@@ -127,6 +130,7 @@ fn load_for_consumer(load_data: LoadData,
             send_error(url, "too many redirects".to_owned(), start_chan)
         }
         Err(LoadError::Cors(url, msg)) |
+        Err(LoadError::Cancelled(url, msg)) |
         Err(LoadError::InvalidRedirect(url, msg)) |
         Err(LoadError::Decoding(url, msg)) => {
             send_error(url, msg, start_chan)
@@ -143,7 +147,7 @@ fn load_for_consumer(load_data: LoadData,
         Err(LoadError::ConnectionAborted(_)) => unreachable!(),
         Ok(mut load_response) => {
             let metadata = load_response.metadata.clone();
-            send_data(&mut load_response, start_chan, metadata, classifier, cancel_listener)
+            send_data(&mut load_response, start_chan, metadata, classifier, &cancel_listener)
         }
     }
 }
@@ -291,6 +295,7 @@ pub enum LoadError {
     Decoding(Url, String),
     MaxRedirects(Url),
     ConnectionAborted(String),
+    Cancelled(Url, String),
 }
 
 fn set_default_accept_encoding(headers: &mut Headers) {
@@ -516,7 +521,8 @@ pub fn load<A>(load_data: LoadData,
                cookie_jar: Arc<RwLock<CookieStorage>>,
                devtools_chan: Option<Sender<DevtoolsControlMsg>>,
                request_factory: &HttpRequestFactory<R=A>,
-               user_agent: String)
+               user_agent: String,
+               cancel_listener: &CancellationListener)
                -> Result<StreamedResponse<A::R>, LoadError> where A: HttpRequest + 'static {
     // FIXME: At the time of writing this FIXME, servo didn't have any central
     //        location for configuration. If you're reading this and such a
@@ -531,6 +537,10 @@ pub fn load<A>(load_data: LoadData,
     let mut redirected_to = HashSet::new();
     let mut method = load_data.method.clone();
 
+    if cancel_listener.is_cancelled() {
+        return Err(LoadError::Cancelled(url, "load cancelled".to_owned()));
+    }
+
     // If the URL is a view-source scheme then the scheme data contains the
     // real URL that should be used for which the source is to be viewed.
     // Change our existing URL to that and keep note that we are viewing
@@ -558,6 +568,10 @@ pub fn load<A>(load_data: LoadData,
             return Err(LoadError::UnsupportedScheme(url));
         }
 
+        if cancel_listener.is_cancelled() {
+            return Err(LoadError::Cancelled(url, "load cancelled".to_owned()));
+        }
+
         info!("requesting {}", url.serialize());
 
         // Avoid automatically preserving request headers when redirects occur.
@@ -586,6 +600,10 @@ pub fn load<A>(load_data: LoadData,
             let mut req = try!(request_factory.create(url.clone(), method.clone()));
             *req.headers_mut() = request_headers.clone();
 
+            if cancel_listener.is_cancelled() {
+                return Err(LoadError::Cancelled(url, "load cancelled".to_owned()));
+            }
+
             if log_enabled!(log::LogLevel::Info) {
                 info!("{}", method);
                 for header in req.headers_mut().iter() {
@@ -623,7 +641,7 @@ pub fn load<A>(load_data: LoadData,
                     method.clone(), request_headers.clone(),
                     cloned_data, pipeline_id
                 );
-}
+            }
 
             response = match maybe_response {
                 Ok(r) => r,
@@ -715,7 +733,7 @@ fn send_data<R: Read>(reader: &mut R,
                       start_chan: LoadConsumer,
                       metadata: Metadata,
                       classifier: Arc<MIMEClassifier>,
-                      cancel_listener: CancellationListener) {
+                      cancel_listener: &CancellationListener) {
     let (progress_chan, mut chunk) = {
         let buf = match read_block(reader) {
             Ok(ReadResult::Payload(buf)) => buf,

components/net/resource_task.rs

@@ -208,6 +208,16 @@ pub struct CancellableResource {
     resource_task: ResourceTask,
 }
 
+impl CancellableResource {
+    pub fn new(receiver: Receiver<()>, res_id: ResourceId, res_task: ResourceTask) -> CancellableResource {
+        CancellableResource {
+            cancel_receiver: receiver,
+            resource_id: res_id,
+            resource_task: res_task,
+        }
+    }
+}
+
 /// A listener which is basically a wrapped optional receiver which looks
 /// for the load cancellation message. Some of the loading processes always keep
 /// an eye out for this message and stop loading stuff once they receive it.
@@ -313,11 +323,7 @@ impl ResourceManager {
             let (cancel_sender, cancel_receiver) = channel();
             self.cancel_load_map.insert(current_res_id, cancel_sender);
             self.next_resource_id.0 += 1;
-            CancellableResource {
-                cancel_receiver: cancel_receiver,
-                resource_id: current_res_id,
-                resource_task: resource_task,
-            }
+            CancellableResource::new(cancel_receiver, current_res_id, resource_task)
         });
 
         let cancel_listener = CancellationListener::new(cancel_resource);