1 files changed, 284 insertions, 0 deletions
diff --git a/toolkit/jetpack/sdk/remote/child.js b/toolkit/jetpack/sdk/remote/child.js
new file mode 100644
index 000000000..4ccfa661a
--- /dev/null
+++ b/toolkit/jetpack/sdk/remote/child.js
@@ -0,0 +1,284 @@
+/* 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/. */
+"use strict";
+
+const { isChildLoader } = require('./core');
+if (!isChildLoader)
+  throw new Error("Cannot load sdk/remote/child in a main process loader.");
+
+const { Ci, Cc, Cu } = require('chrome');
+const runtime = require('../system/runtime');
+const { Class } = require('../core/heritage');
+const { Namespace } = require('../core/namespace');
+const { omit } = require('../util/object');
+const { when } = require('../system/unload');
+const { EventTarget } = require('../event/target');
+const { emit } = require('../event/core');
+const { Disposable } = require('../core/disposable');
+const { EventParent } = require('./utils');
+const { addListItem, removeListItem } = require('../util/list');
+
+const loaderID = require('@loader/options').loaderID;
+
+const MAIN_PROCESS = Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT;
+
+const mm = Cc['@mozilla.org/childprocessmessagemanager;1'].
+           getService(Ci.nsISyncMessageSender);
+
+const ns = Namespace();
+
+const process = {
+  port: new EventTarget(),
+  get id() {
+    return runtime.processID;
+  },
+  get isRemote() {
+    return runtime.processType != MAIN_PROCESS;
+  }
+};
+exports.process = process;
+
+function definePort(obj, name) {
+  obj.port.emit = (event, ...args) => {
+    let manager = ns(obj).messageManager;
+    if (!manager)
+      return;
+
+    manager.sendAsyncMessage(name, { loaderID, event, args });
+  };
+}
+
+function messageReceived({ data, objects }) {
+  // Ignore messages from other loaders
+  if (data.loaderID != loaderID)
+    return;
+
+  let keys = Object.keys(objects);
+  if (keys.length) {
+    // If any objects are CPOWs then ignore this message. We don't want child
+    // processes interracting with CPOWs
+    if (!keys.every(name => !Cu.isCrossProcessWrapper(objects[name])))
+      return;
+
+    data.args.push(objects);
+  }
+
+  emit(this.port, data.event, this, ...data.args);
+}
+
+ns(process).messageManager = mm;
+definePort(process, 'sdk/remote/process/message');
+let processMessageReceived = messageReceived.bind(process);
+mm.addMessageListener('sdk/remote/process/message', processMessageReceived);
+
+when(() => {
+  mm.removeMessageListener('sdk/remote/process/message', processMessageReceived);
+  frames = null;
+});
+
+process.port.on('sdk/remote/require', (process, uri) => {
+  require(uri);
+});
+
+function listenerEquals(a, b) {
+  for (let prop of ["type", "callback", "isCapturing"]) {
+    if (a[prop] != b[prop])
+      return false;
+  }
+  return true;
+}
+
+function listenerFor(type, callback, isCapturing = false) {
+  return {
+    type,
+    callback,
+    isCapturing,
+    registeredCallback: undefined,
+    get args() {
+      return [
+        this.type,
+        this.registeredCallback ? this.registeredCallback : this.callback,
+        this.isCapturing
+      ];
+    }
+  };
+}
+
+function removeListenerFromArray(array, listener) {
+  let index = array.findIndex(l => listenerEquals(l, listener));
+  if (index < 0)
+    return;
+  array.splice(index, 1);
+}
+
+function getListenerFromArray(array, listener) {
+  return array.find(l => listenerEquals(l, listener));
+}
+
+function arrayContainsListener(array, listener) {
+  return !!getListenerFromArray(array, listener);
+}
+
+function makeFrameEventListener(frame, callback) {
+  return callback.bind(frame);
+}
+
+var FRAME_ID = 0;
+var tabMap = new Map();
+
+const Frame = Class({
+  implements: [ Disposable ],
+  extends: EventTarget,
+  setup: function(contentFrame) {
+    // This ID should be unique for this loader across all processes
+    let priv = ns(this);
+
+    priv.id = runtime.processID + ":" + FRAME_ID++;
+
+    priv.contentFrame = contentFrame;
+    priv.messageManager = contentFrame;
+    priv.domListeners = [];
+
+    tabMap.set(contentFrame.docShell, this);
+
+    priv.messageReceived = messageReceived.bind(this);
+    priv.messageManager.addMessageListener('sdk/remote/frame/message', priv.messageReceived);
+
+    this.port = new EventTarget();
+    definePort(this, 'sdk/remote/frame/message');
+
+    priv.messageManager.sendAsyncMessage('sdk/remote/frame/attach', {
+      loaderID,
+      frameID: priv.id,
+      processID: runtime.processID
+    });
+
+    frames.attachItem(this);
+  },
+
+  dispose: function() {
+    let priv = ns(this);
+
+    emit(this, 'detach', this);
+
+    for (let listener of priv.domListeners)
+      priv.contentFrame.removeEventListener(...listener.args);
+
+    priv.messageManager.removeMessageListener('sdk/remote/frame/message', priv.messageReceived);
+    tabMap.delete(priv.contentFrame.docShell);
+    priv.contentFrame = null;
+  },
+
+  get content() {
+    return ns(this).contentFrame.content;
+  },
+
+  get isTab() {
+    let docShell = ns(this).contentFrame.docShell;
+    if (process.isRemote) {
+      // We don't want to roundtrip to the main process to get this property.
+      // This hack relies on the host app having defined webBrowserChrome only
+      // in frames that are part of the tabs. Since only Firefox has remote
+      // processes right now and does this this works.
+      let tabchild = docShell.QueryInterface(Ci.nsIInterfaceRequestor)
+                             .getInterface(Ci.nsITabChild);
+      return !!tabchild.webBrowserChrome;
+    }
+    else {
+      // This is running in the main process so we can break out to the browser
+      // And check we can find a tab for the browser element directly.
+      let browser = docShell.chromeEventHandler;
+      let tab = require('../tabs/utils').getTabForBrowser(browser);
+      return !!tab;
+    }
+  },
+
+  addEventListener: function(...args) {
+    let priv = ns(this);
+
+    let listener = listenerFor(...args);
+    if (arrayContainsListener(priv.domListeners, listener))
+      return;
+
+    listener.registeredCallback = makeFrameEventListener(this, listener.callback);
+
+    priv.domListeners.push(listener);
+    priv.contentFrame.addEventListener(...listener.args);
+  },
+
+  removeEventListener: function(...args) {
+    let priv = ns(this);
+
+    let listener = getListenerFromArray(priv.domListeners, listenerFor(...args));
+    if (!listener)
+      return;
+
+    removeListenerFromArray(priv.domListeners, listener);
+    priv.contentFrame.removeEventListener(...listener.args);
+  }
+});
+
+const FrameList = Class({
+  implements: [ EventParent, Disposable ],
+  extends: EventTarget,
+  setup: function() {
+    EventParent.prototype.initialize.call(this);
+
+    this.port = new EventTarget();
+    ns(this).domListeners = [];
+
+    this.on('attach', frame => {
+      for (let listener of ns(this).domListeners)
+        frame.addEventListener(...listener.args);
+    });
+  },
+
+  dispose: function() {
+    // The only case where we get destroyed is when the loader is unloaded in
+    // which case each frame will clean up its own event listeners.
+    ns(this).domListeners = null;
+  },
+
+  getFrameForWindow: function(window) {
+    let docShell = window.QueryInterface(Ci.nsIInterfaceRequestor)
+                         .getInterface(Ci.nsIDocShell);
+
+    return tabMap.get(docShell) || null;
+  },
+
+  addEventListener: function(...args) {
+    let listener = listenerFor(...args);
+    if (arrayContainsListener(ns(this).domListeners, listener))
+      return;
+
+    ns(this).domListeners.push(listener);
+    for (let frame of this)
+      frame.addEventListener(...listener.args);
+  },
+
+  removeEventListener: function(...args) {
+    let listener = listenerFor(...args);
+    if (!arrayContainsListener(ns(this).domListeners, listener))
+      return;
+
+    removeListenerFromArray(ns(this).domListeners, listener);
+    for (let frame of this)
+      frame.removeEventListener(...listener.args);
+  }
+});
+var frames = exports.frames = new FrameList();
+
+function registerContentFrame(contentFrame) {
+  let frame = new Frame(contentFrame);
+}
+exports.registerContentFrame = registerContentFrame;
+
+function unregisterContentFrame(contentFrame) {
+  let frame = tabMap.get(contentFrame.docShell);
+  if (!frame)
+    return;
+
+  frame.destroy();
+}
+exports.unregisterContentFrame = unregisterContentFrame;