Refactor constellation broadcast channel (#38077)

- Move the 2 hash maps used to manage channels in their own struct.
- The constellation is still in charge of origin checks since it holds
the pipeline information required.
- BroadcastMsg is renamed to BroadcastChannelMsg for consistency.


Testing: covered by existing tests.
Fixes: #38060

Signed-off-by: webbeef <me@webbeef.org>

components/constellation/broadcastchannel.rs

@@ -0,0 +1,129 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+use std::collections::HashMap;
+
+use base::id::BroadcastChannelRouterId;
+use constellation_traits::BroadcastChannelMsg;
+use ipc_channel::ipc::IpcSender;
+use log::warn;
+use servo_url::ImmutableOrigin;
+
+#[derive(Default)]
+pub(crate) struct BroadcastChannels {
+    /// A map of broadcast routers to their IPC sender.
+    routers: HashMap<BroadcastChannelRouterId, IpcSender<BroadcastChannelMsg>>,
+
+    /// A map of origin to a map of channel name to a list of relevant routers.
+    channels: HashMap<ImmutableOrigin, HashMap<String, Vec<BroadcastChannelRouterId>>>,
+}
+
+impl BroadcastChannels {
+    /// Add a new broadcast router.
+    #[servo_tracing::instrument(skip_all)]
+    pub fn new_broadcast_channel_router(
+        &mut self,
+        router_id: BroadcastChannelRouterId,
+        broadcast_ipc_sender: IpcSender<BroadcastChannelMsg>,
+    ) {
+        if self
+            .routers
+            .insert(router_id, broadcast_ipc_sender)
+            .is_some()
+        {
+            warn!("Multiple attempts to add BroadcastChannel router.");
+        }
+    }
+
+    /// Remove a broadcast router.
+    #[servo_tracing::instrument(skip_all)]
+    pub fn remove_broadcast_channel_router(&mut self, router_id: BroadcastChannelRouterId) {
+        if self.routers.remove(&router_id).is_none() {
+            warn!("Attempt to remove unknown BroadcastChannel router.");
+        }
+        // Also remove the router_id from the broadcast_channels list.
+        for channels in self.channels.values_mut() {
+            for routers in channels.values_mut() {
+                routers.retain(|router| router != &router_id);
+            }
+        }
+    }
+
+    /// Note a new channel-name relevant to a given broadcast router.
+    #[servo_tracing::instrument(skip_all)]
+    pub fn new_broadcast_channel_name_in_router(
+        &mut self,
+        router_id: BroadcastChannelRouterId,
+        channel_name: String,
+        origin: ImmutableOrigin,
+    ) {
+        let channels = self.channels.entry(origin).or_default();
+        let routers = channels.entry(channel_name).or_default();
+        routers.push(router_id);
+    }
+
+    /// Remove a channel-name for a given broadcast router.
+    #[servo_tracing::instrument(skip_all)]
+    pub fn remove_broadcast_channel_name_in_router(
+        &mut self,
+        router_id: BroadcastChannelRouterId,
+        channel_name: String,
+        origin: ImmutableOrigin,
+    ) {
+        if let Some(channels) = self.channels.get_mut(&origin) {
+            let is_empty = if let Some(routers) = channels.get_mut(&channel_name) {
+                routers.retain(|router| router != &router_id);
+                routers.is_empty()
+            } else {
+                return warn!(
+                    "Multiple attempts to remove name for BroadcastChannel {:?} at {:?}",
+                    channel_name, origin
+                );
+            };
+            if is_empty {
+                channels.remove(&channel_name);
+            }
+        } else {
+            warn!(
+                "Attempt to remove a channel name for an origin without channels {:?}",
+                origin
+            );
+        }
+    }
+
+    /// Broadcast a message via routers in various event-loops.
+    #[servo_tracing::instrument(skip_all)]
+    pub fn schedule_broadcast(
+        &self,
+        router_id: BroadcastChannelRouterId,
+        message: BroadcastChannelMsg,
+    ) {
+        if let Some(channels) = self.channels.get(&message.origin) {
+            let routers = match channels.get(&message.channel_name) {
+                Some(routers) => routers,
+                None => return warn!("Broadcast to channel name without active routers."),
+            };
+            for router in routers {
+                // Exclude the sender of the broadcast.
+                // Broadcasting locally is done at the point of sending.
+                if router == &router_id {
+                    continue;
+                }
+
+                if let Some(broadcast_ipc_sender) = self.routers.get(router) {
+                    if broadcast_ipc_sender.send(message.clone()).is_err() {
+                        warn!("Failed to broadcast message to router: {:?}", router);
+                    }
+                } else {
+                    warn!("No sender for broadcast router: {:?}", router);
+                }
+            }
+        } else {
+            warn!(
+                "Attempt to schedule a broadcast for an origin without routers {:?}",
+                message.origin
+            );
+        }
+    }
+}

components/constellation/constellation.rs

@@ -100,9 +100,8 @@ use background_hang_monitor_api::{
 };
 use base::Epoch;
 use base::id::{
-    BroadcastChannelRouterId, BrowsingContextGroupId, BrowsingContextId, HistoryStateId,
-    MessagePortId, MessagePortRouterId, PipelineId, PipelineNamespace, PipelineNamespaceId,
-    PipelineNamespaceRequest, WebViewId,
+    BrowsingContextGroupId, BrowsingContextId, HistoryStateId, MessagePortId, MessagePortRouterId,
+    PipelineId, PipelineNamespace, PipelineNamespaceId, PipelineNamespaceRequest, WebViewId,
 };
 #[cfg(feature = "bluetooth")]
 use bluetooth_traits::BluetoothRequest;
@@ -115,7 +114,7 @@ use compositing_traits::{
     WebrenderExternalImageRegistry,
 };
 use constellation_traits::{
-    AuxiliaryWebViewCreationRequest, AuxiliaryWebViewCreationResponse, BroadcastMsg, DocumentState,
+    AuxiliaryWebViewCreationRequest, AuxiliaryWebViewCreationResponse, DocumentState,
     EmbedderToConstellationMessage, IFrameLoadInfo, IFrameLoadInfoWithData, IFrameSandboxState,
     IFrameSizeMsg, Job, LoadData, LoadOrigin, LogEntry, MessagePortMsg, NavigationHistoryBehavior,
     PaintMetricEvent, PortMessageTask, PortTransferInfo, SWManagerMsg, SWManagerSenders,
@@ -169,6 +168,7 @@ use webrender::RenderApiSender;
 use webrender_api::units::LayoutVector2D;
 use webrender_api::{DocumentId, ExternalScrollId, ImageKey};
 
+use crate::broadcastchannel::BroadcastChannels;
 use crate::browsingcontext::{
     AllBrowsingContextsIterator, BrowsingContext, FullyActiveBrowsingContextsIterator,
     NewBrowsingContextInfo,
@@ -368,11 +368,8 @@ pub struct Constellation<STF, SWF> {
     /// A map of router-id to ipc-sender, to route messages to ports.
     message_port_routers: HashMap<MessagePortRouterId, IpcSender<MessagePortMsg>>,
 
-    /// A map of broadcast routers to their IPC sender.
-    broadcast_routers: HashMap<BroadcastChannelRouterId, IpcSender<BroadcastMsg>>,
-
-    /// A map of origin to a map of channel-name to a list of relevant routers.
-    broadcast_channels: HashMap<ImmutableOrigin, HashMap<String, Vec<BroadcastChannelRouterId>>>,
+    /// Bookkeeping for BroadcastChannel functionnality.
+    broadcast_channels: BroadcastChannels,
 
     /// The set of all the pipelines in the browser.  (See the `pipeline` module
     /// for more details.)
@@ -678,8 +675,7 @@ where
                     browsing_context_group_next_id: Default::default(),
                     message_ports: HashMap::new(),
                     message_port_routers: HashMap::new(),
-                    broadcast_routers: HashMap::new(),
-                    broadcast_channels: HashMap::new(),
+                    broadcast_channels: Default::default(),
                     pipelines: HashMap::new(),
                     browsing_contexts: HashMap::new(),
                     pending_changes: vec![],
@@ -1570,42 +1566,64 @@ where
                 response_sender,
                 origin,
             ) => {
-                self.handle_new_broadcast_channel_router(
-                    source_pipeline_id,
-                    router_id,
-                    response_sender,
-                    origin,
-                );
+                if self
+                    .check_origin_against_pipeline(&source_pipeline_id, &origin)
+                    .is_err()
+                {
+                    return warn!("Attempt to add broadcast router from an unexpected origin.");
+                }
+                self.broadcast_channels
+                    .new_broadcast_channel_router(router_id, response_sender);
             },
             ScriptToConstellationMessage::NewBroadcastChannelNameInRouter(
                 router_id,
                 channel_name,
                 origin,
             ) => {
-                self.handle_new_broadcast_channel_name_in_router(
-                    source_pipeline_id,
-                    router_id,
-                    channel_name,
-                    origin,
-                );
+                if self
+                    .check_origin_against_pipeline(&source_pipeline_id, &origin)
+                    .is_err()
+                {
+                    return warn!("Attempt to add channel name from an unexpected origin.");
+                }
+                self.broadcast_channels
+                    .new_broadcast_channel_name_in_router(router_id, channel_name, origin);
             },
             ScriptToConstellationMessage::RemoveBroadcastChannelNameInRouter(
                 router_id,
                 channel_name,
                 origin,
             ) => {
-                self.handle_remove_broadcast_channel_name_in_router(
-                    source_pipeline_id,
-                    router_id,
-                    channel_name,
-                    origin,
-                );
+                if self
+                    .check_origin_against_pipeline(&source_pipeline_id, &origin)
+                    .is_err()
+                {
+                    return warn!("Attempt to remove channel name from an unexpected origin.");
+                }
+                self.broadcast_channels
+                    .remove_broadcast_channel_name_in_router(router_id, channel_name, origin);
             },
             ScriptToConstellationMessage::RemoveBroadcastChannelRouter(router_id, origin) => {
-                self.handle_remove_broadcast_channel_router(source_pipeline_id, router_id, origin);
+                if self
+                    .check_origin_against_pipeline(&source_pipeline_id, &origin)
+                    .is_err()
+                {
+                    return warn!("Attempt to remove broadcast router from an unexpected origin.");
+                }
+                self.broadcast_channels
+                    .remove_broadcast_channel_router(router_id);
             },
             ScriptToConstellationMessage::ScheduleBroadcast(router_id, message) => {
-                self.handle_schedule_broadcast(source_pipeline_id, router_id, message);
+                if self
+                    .check_origin_against_pipeline(&source_pipeline_id, &message.origin)
+                    .is_err()
+                {
+                    return warn!(
+                        "Attempt to schedule broadcast from an origin not matching the origin of the msg."
+                    );
+                }
+                self.broadcast_channels
+                    .schedule_broadcast(router_id, message);
             },
             ScriptToConstellationMessage::ForwardToEmbedder(embedder_msg) => {
                 self.embedder_proxy.send(embedder_msg);
@@ -1890,157 +1908,6 @@ where
         Err(())
     }
 
-    /// Broadcast a message via routers in various event-loops.
-    #[servo_tracing::instrument(skip_all)]
-    fn handle_schedule_broadcast(
-        &self,
-        pipeline_id: PipelineId,
-        router_id: BroadcastChannelRouterId,
-        message: BroadcastMsg,
-    ) {
-        if self
-            .check_origin_against_pipeline(&pipeline_id, &message.origin)
-            .is_err()
-        {
-            return warn!(
-                "Attempt to schedule broadcast from an origin not matching the origin of the msg."
-            );
-        }
-        if let Some(channels) = self.broadcast_channels.get(&message.origin) {
-            let routers = match channels.get(&message.channel_name) {
-                Some(routers) => routers,
-                None => return warn!("Broadcast to channel name without active routers."),
-            };
-            for router in routers {
-                // Exclude the sender of the broadcast.
-                // Broadcasting locally is done at the point of sending.
-                if router == &router_id {
-                    continue;
-                }
-
-                if let Some(broadcast_ipc_sender) = self.broadcast_routers.get(router) {
-                    if broadcast_ipc_sender.send(message.clone()).is_err() {
-                        warn!("Failed to broadcast message to router: {:?}", router);
-                    }
-                } else {
-                    warn!("No sender for broadcast router: {:?}", router);
-                }
-            }
-        } else {
-            warn!(
-                "Attempt to schedule a broadcast for an origin without routers {:?}",
-                message.origin
-            );
-        }
-    }
-
-    /// Remove a channel-name for a given broadcast router.
-    #[servo_tracing::instrument(skip_all)]
-    fn handle_remove_broadcast_channel_name_in_router(
-        &mut self,
-        pipeline_id: PipelineId,
-        router_id: BroadcastChannelRouterId,
-        channel_name: String,
-        origin: ImmutableOrigin,
-    ) {
-        if self
-            .check_origin_against_pipeline(&pipeline_id, &origin)
-            .is_err()
-        {
-            return warn!("Attempt to remove channel name from an unexpected origin.");
-        }
-        if let Some(channels) = self.broadcast_channels.get_mut(&origin) {
-            let is_empty = if let Some(routers) = channels.get_mut(&channel_name) {
-                routers.retain(|router| router != &router_id);
-                routers.is_empty()
-            } else {
-                return warn!(
-                    "Multiple attempts to remove name for broadcast-channel {:?} at {:?}",
-                    channel_name, origin
-                );
-            };
-            if is_empty {
-                channels.remove(&channel_name);
-            }
-        } else {
-            warn!(
-                "Attempt to remove a channel-name for an origin without channels {:?}",
-                origin
-            );
-        }
-    }
-
-    /// Note a new channel-name relevant to a given broadcast router.
-    #[servo_tracing::instrument(skip_all)]
-    fn handle_new_broadcast_channel_name_in_router(
-        &mut self,
-        pipeline_id: PipelineId,
-        router_id: BroadcastChannelRouterId,
-        channel_name: String,
-        origin: ImmutableOrigin,
-    ) {
-        if self
-            .check_origin_against_pipeline(&pipeline_id, &origin)
-            .is_err()
-        {
-            return warn!("Attempt to add channel name from an unexpected origin.");
-        }
-        let channels = self.broadcast_channels.entry(origin).or_default();
-
-        let routers = channels.entry(channel_name).or_default();
-
-        routers.push(router_id);
-    }
-
-    /// Remove a broadcast router.
-    #[servo_tracing::instrument(skip_all)]
-    fn handle_remove_broadcast_channel_router(
-        &mut self,
-        pipeline_id: PipelineId,
-        router_id: BroadcastChannelRouterId,
-        origin: ImmutableOrigin,
-    ) {
-        if self
-            .check_origin_against_pipeline(&pipeline_id, &origin)
-            .is_err()
-        {
-            return warn!("Attempt to remove broadcast router from an unexpected origin.");
-        }
-        if self.broadcast_routers.remove(&router_id).is_none() {
-            warn!("Attempt to remove unknown broadcast-channel router.");
-        }
-        // Also remove the router_id from the broadcast_channels list.
-        for channels in self.broadcast_channels.values_mut() {
-            for routers in channels.values_mut() {
-                routers.retain(|router| router != &router_id);
-            }
-        }
-    }
-
-    /// Add a new broadcast router.
-    #[servo_tracing::instrument(skip_all)]
-    fn handle_new_broadcast_channel_router(
-        &mut self,
-        pipeline_id: PipelineId,
-        router_id: BroadcastChannelRouterId,
-        broadcast_ipc_sender: IpcSender<BroadcastMsg>,
-        origin: ImmutableOrigin,
-    ) {
-        if self
-            .check_origin_against_pipeline(&pipeline_id, &origin)
-            .is_err()
-        {
-            return warn!("Attempt to add broadcast router from an unexpected origin.");
-        }
-        if self
-            .broadcast_routers
-            .insert(router_id, broadcast_ipc_sender)
-            .is_some()
-        {
-            warn!("Multple attempt to add broadcast-channel router.");
-        }
-    }
-
     #[servo_tracing::instrument(skip_all)]
     #[cfg(feature = "webgpu")]
     fn handle_wgpu_request(

components/constellation/lib.rs

@@ -7,6 +7,7 @@
 #[macro_use]
 mod tracing;
 
+mod broadcastchannel;
 mod browsingcontext;
 mod constellation;
 mod constellation_webview;

components/script/dom/broadcastchannel.rs

@@ -4,7 +4,7 @@
 
 use std::cell::Cell;
 
-use constellation_traits::BroadcastMsg;
+use constellation_traits::BroadcastChannelMsg;
 use dom_struct::dom_struct;
 use js::rust::{HandleObject, HandleValue};
 use uuid::Uuid;
@@ -89,7 +89,7 @@ impl BroadcastChannelMethods<crate::DomTypeHolder> for BroadcastChannel {
 
         let global = self.global();
 
-        let msg = BroadcastMsg {
+        let msg = BroadcastChannelMsg {
             origin: global.origin().immutable().clone(),
             channel_name: self.Name().to_string(),
             data,

components/script/dom/globalscope.rs

@@ -18,8 +18,8 @@ use base::id::{
     ServiceWorkerId, ServiceWorkerRegistrationId, WebViewId,
 };
 use constellation_traits::{
-    BlobData, BlobImpl, BroadcastMsg, FileBlob, MessagePortImpl, MessagePortMsg, PortMessageTask,
-    ScriptToConstellationChan, ScriptToConstellationMessage,
+    BlobData, BlobImpl, BroadcastChannelMsg, FileBlob, MessagePortImpl, MessagePortMsg,
+    PortMessageTask, ScriptToConstellationChan, ScriptToConstellationMessage,
 };
 use content_security_policy::CspList;
 use crossbeam_channel::Sender;
@@ -501,7 +501,7 @@ pub(crate) enum MessagePortState {
 impl BroadcastListener {
     /// Handle a broadcast coming in over IPC,
     /// by queueing the appropriate task on the relevant event-loop.
-    fn handle(&self, event: BroadcastMsg) {
+    fn handle(&self, event: BroadcastChannelMsg) {
         let context = self.context.clone();
 
         // Note: strictly speaking we should just queue the message event tasks,
@@ -1223,7 +1223,7 @@ impl GlobalScope {
 
     /// <https://html.spec.whatwg.org/multipage/#dom-broadcastchannel-postmessage>
     /// Step 7 and following steps.
-    pub(crate) fn schedule_broadcast(&self, msg: BroadcastMsg, channel_id: &Uuid) {
+    pub(crate) fn schedule_broadcast(&self, msg: BroadcastChannelMsg, channel_id: &Uuid) {
         // First, broadcast locally.
         self.broadcast_message_event(msg.clone(), Some(channel_id));
 
@@ -1244,10 +1244,14 @@ impl GlobalScope {
 
     /// <https://html.spec.whatwg.org/multipage/#dom-broadcastchannel-postmessage>
     /// Step 7 and following steps.
-    pub(crate) fn broadcast_message_event(&self, event: BroadcastMsg, channel_id: Option<&Uuid>) {
+    pub(crate) fn broadcast_message_event(
+        &self,
+        event: BroadcastChannelMsg,
+        channel_id: Option<&Uuid>,
+    ) {
         if let BroadcastChannelState::Managed(_, channels) = &*self.broadcast_channel_state.borrow()
         {
-            let BroadcastMsg {
+            let BroadcastChannelMsg {
                 data,
                 origin,
                 channel_name,
@@ -1617,7 +1621,7 @@ impl GlobalScope {
                 broadcast_control_receiver,
                 Box::new(move |message| match message {
                     Ok(msg) => listener.handle(msg),
-                    Err(err) => warn!("Error receiving a BroadcastMsg: {:?}", err),
+                    Err(err) => warn!("Error receiving a BroadcastChannelMsg: {:?}", err),
                 }),
             );
             let router_id = BroadcastChannelRouterId::new();

components/shared/constellation/from_script_message.rs

@@ -36,7 +36,7 @@ use strum_macros::IntoStaticStr;
 use webgpu_traits::{WebGPU, WebGPUAdapterResponse};
 use webrender_api::ImageKey;
 
-use crate::structured_data::{BroadcastMsg, StructuredSerializedData};
+use crate::structured_data::{BroadcastChannelMsg, StructuredSerializedData};
 use crate::{
     LogEntry, MessagePortMsg, PortMessageTask, PortTransferInfo, TraversalDirection, WindowSizeType,
 };
@@ -506,7 +506,7 @@ pub enum ScriptToConstellationMessage {
     /// A global has started managing broadcast-channels.
     NewBroadcastChannelRouter(
         BroadcastChannelRouterId,
-        IpcSender<BroadcastMsg>,
+        IpcSender<BroadcastChannelMsg>,
         ImmutableOrigin,
     ),
     /// A global has stopped managing broadcast-channels.
@@ -517,7 +517,7 @@ pub enum ScriptToConstellationMessage {
     RemoveBroadcastChannelNameInRouter(BroadcastChannelRouterId, String, ImmutableOrigin),
     /// Broadcast a message to all same-origin broadcast channels,
     /// excluding the source of the broadcast.
-    ScheduleBroadcast(BroadcastChannelRouterId, BroadcastMsg),
+    ScheduleBroadcast(BroadcastChannelRouterId, BroadcastChannelMsg),
     /// Forward a message to the embedder.
     ForwardToEmbedder(EmbedderMsg),
     /// Broadcast a storage event to every same-origin pipeline.

components/shared/constellation/structured_data/serializable.rs

@@ -74,7 +74,7 @@ impl Serializable {
 
 /// Message for communication between the constellation and a global managing broadcast channels.
 #[derive(Debug, Deserialize, Serialize)]
-pub struct BroadcastMsg {
+pub struct BroadcastChannelMsg {
     /// The origin of this message.
     pub origin: ImmutableOrigin,
     /// The name of the channel.
@@ -83,9 +83,9 @@ pub struct BroadcastMsg {
     pub data: StructuredSerializedData,
 }
 
-impl Clone for BroadcastMsg {
-    fn clone(&self) -> BroadcastMsg {
-        BroadcastMsg {
+impl Clone for BroadcastChannelMsg {
+    fn clone(&self) -> BroadcastChannelMsg {
+        BroadcastChannelMsg {
             data: self.data.clone_for_broadcast(),
             origin: self.origin.clone(),
             channel_name: self.channel_name.clone(),