1 files changed, 145 insertions, 0 deletions
diff --git a/devtools/server/actors/monitor.js b/devtools/server/actors/monitor.js
new file mode 100644
index 000000000..17b076a9e
--- /dev/null
+++ b/devtools/server/actors/monitor.js
@@ -0,0 +1,145 @@
+/* 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 {Ci, Cc} = require("chrome");
+const {XPCOMUtils} = require("resource://gre/modules/XPCOMUtils.jsm");
+const Services = require("Services");
+
+function MonitorActor(aConnection) {
+  this.conn = aConnection;
+  this._updates = [];
+  this._started = false;
+}
+
+MonitorActor.prototype = {
+  actorPrefix: "monitor",
+
+  // Updates.
+
+  _sendUpdate: function () {
+    if (this._started) {
+      this.conn.sendActorEvent(this.actorID, "update", { data: this._updates });
+      this._updates = [];
+    }
+  },
+
+  // Methods available from the front.
+
+  start: function () {
+    if (!this._started) {
+      this._started = true;
+      Services.obs.addObserver(this, "devtools-monitor-update", false);
+      Services.obs.notifyObservers(null, "devtools-monitor-start", "");
+      this._agents.forEach(agent => this._startAgent(agent));
+    }
+    return {};
+  },
+
+  stop: function () {
+    if (this._started) {
+      this._agents.forEach(agent => agent.stop());
+      Services.obs.notifyObservers(null, "devtools-monitor-stop", "");
+      Services.obs.removeObserver(this, "devtools-monitor-update");
+      this._started = false;
+    }
+    return {};
+  },
+
+  disconnect: function () {
+    this.stop();
+  },
+
+  // nsIObserver.
+
+  observe: function (subject, topic, data) {
+    if (topic == "devtools-monitor-update") {
+      try {
+        data = JSON.parse(data);
+      } catch (e) {
+        console.error("Observer notification data is not a valid JSON-string:",
+                      data, e.message);
+        return;
+      }
+      if (!Array.isArray(data)) {
+        this._updates.push(data);
+      } else {
+        this._updates = this._updates.concat(data);
+      }
+      this._sendUpdate();
+    }
+  },
+
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver]),
+
+  // Update agents (see USSAgent for an example).
+
+  _agents: [],
+
+  _startAgent: function (agent) {
+    try {
+      agent.start();
+    } catch (e) {
+      this._removeAgent(agent);
+    }
+  },
+
+  _addAgent: function (agent) {
+    this._agents.push(agent);
+    if (this._started) {
+      this._startAgent(agent);
+    }
+  },
+
+  _removeAgent: function (agent) {
+    let index = this._agents.indexOf(agent);
+    if (index > -1) {
+      this._agents.splice(index, 1);
+    }
+  },
+};
+
+MonitorActor.prototype.requestTypes = {
+  "start": MonitorActor.prototype.start,
+  "stop": MonitorActor.prototype.stop,
+};
+
+exports.MonitorActor = MonitorActor;
+
+var USSAgent = {
+  _mgr: null,
+  _timeout: null,
+  _packet: {
+    graph: "USS",
+    time: null,
+    value: null
+  },
+
+  start: function () {
+    USSAgent._mgr = Cc["@mozilla.org/memory-reporter-manager;1"].getService(Ci.nsIMemoryReporterManager);
+    if (!USSAgent._mgr.residentUnique) {
+      throw "Couldn't get USS.";
+    }
+    USSAgent.update();
+  },
+
+  update: function () {
+    if (!USSAgent._mgr) {
+      USSAgent.stop();
+      return;
+    }
+    USSAgent._packet.time = Date.now();
+    USSAgent._packet.value = USSAgent._mgr.residentUnique;
+    Services.obs.notifyObservers(null, "devtools-monitor-update", JSON.stringify(USSAgent._packet));
+    USSAgent._timeout = setTimeout(USSAgent.update, 300);
+  },
+
+  stop: function () {
+    clearTimeout(USSAgent._timeout);
+    USSAgent._mgr = null;
+  }
+};
+
+MonitorActor.prototype._addAgent(USSAgent);