diff -r 000000000000 -r 6474c204b198 mobile/android/modules/SimpleServiceDiscovery.jsm
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mobile/android/modules/SimpleServiceDiscovery.jsm	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,286 @@
+// -*- Mode: js2; tab-width: 2; indent-tabs-mode: nil; js2-basic-offset: 2; js2-skip-preprocessor-directives: t; -*-
+/* 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";
+
+this.EXPORTED_SYMBOLS = ["SimpleServiceDiscovery"];
+
+const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
+
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+function log(msg) {
+  Services.console.logStringMessage("[SSDP] " + msg);
+}
+
+XPCOMUtils.defineLazyGetter(this, "converter", function () {
+  let conv = Cc["@mozilla.org/intl/scriptableunicodeconverter"].createInstance(Ci.nsIScriptableUnicodeConverter);
+  conv.charset = "utf8";
+  return conv;
+});
+
+// Spec information:
+// https://tools.ietf.org/html/draft-cai-ssdp-v1-03
+// http://www.dial-multiscreen.org/dial-protocol-specification
+const SSDP_PORT = 1900;
+const SSDP_ADDRESS = "239.255.255.250";
+
+const SSDP_DISCOVER_PACKET =
+  "M-SEARCH * HTTP/1.1\r\n" +
+  "HOST: " + SSDP_ADDRESS + ":" + SSDP_PORT + "\r\n" +
+  "MAN: \"ssdp:discover\"\r\n" +
+  "MX: 2\r\n" +
+  "ST: %SEARCH_TARGET%\r\n\r\n";
+
+const SSDP_DISCOVER_TIMEOUT = 10000;
+
+/*
+ * SimpleServiceDiscovery manages any discovered SSDP services. It uses a UDP
+ * broadcast to locate available services on the local network.
+ */
+var SimpleServiceDiscovery = {
+  _targets: new Map(),
+  _services: new Map(),
+  _searchSocket: null,
+  _searchInterval: 0,
+  _searchTimestamp: 0,
+  _searchTimeout: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
+  _searchRepeat: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
+
+  _forceTrailingSlash: function(aURL) {
+    // Some devices add the trailing '/' and some don't. Let's make sure
+    // it's there for consistency.
+    if (!aURL.endsWith("/")) {
+      aURL += "/";
+    }
+    return aURL;
+  },
+
+  // nsIUDPSocketListener implementation
+  onPacketReceived: function(aSocket, aMessage) {
+    // Listen for responses from specific targets. There could be more than one
+    // available.
+    let response = aMessage.data.split("\n");
+    let location;
+    let target;
+    let valid = false;
+    response.some(function(row) {
+      let header = row.toUpperCase();
+      if (header.startsWith("LOCATION")) {
+        location = row.substr(10).trim();
+      } else if (header.startsWith("ST")) {
+        target = row.substr(4).trim();
+        if (this._targets.has(target)) {
+          valid = true;
+        }
+      }
+
+      if (location && valid) {
+        location = this._forceTrailingSlash(location);
+
+        // When we find a valid response, package up the service information
+        // and pass it on.
+        let service = {
+          location: location,
+          target: target
+        };
+
+        try {
+          this._processService(service);
+        } catch (e) {}
+
+        return true;
+      }
+      return false;
+    }.bind(this));
+  },
+
+  onStopListening: function(aSocket, aStatus) {
+    // This is fired when the socket is closed expectedly or unexpectedly.
+    // nsITimer.cancel() is a no-op if the timer is not active.
+    this._searchTimeout.cancel();
+    this._searchSocket = null;
+  },
+
+  // Start a search. Make it continuous by passing an interval (in milliseconds).
+  // This will stop a current search loop because the timer resets itself.
+  search: function search(aInterval) {
+    if (aInterval > 0) {
+      this._searchInterval = aInterval || 0;
+      this._searchRepeat.initWithCallback(this._search.bind(this), this._searchInterval, Ci.nsITimer.TYPE_REPEATING_SLACK);
+    }
+    this._search();
+  },
+
+  // Stop the current continuous search
+  stopSearch: function stopSearch() {
+    this._searchRepeat.cancel();
+  },
+
+  _usingLAN: function() {
+    let network = Cc["@mozilla.org/network/network-link-service;1"].getService(Ci.nsINetworkLinkService);
+    return (network.linkType == Ci.nsINetworkLinkService.LINK_TYPE_WIFI || network.linkType == Ci.nsINetworkLinkService.LINK_TYPE_ETHERNET);
+  },
+
+  _search: function _search() {
+    // If a search is already active, shut it down.
+    this._searchShutdown();
+
+    // We only search if on local network
+    if (!this._usingLAN()) {
+      return;
+    }
+
+    // Update the timestamp so we can use it to clean out stale services the
+    // next time we search.
+    this._searchTimestamp = Date.now();
+
+    // Look for any fixed IP targets. Some routers might be configured to block
+    // UDP broadcasts, so this is a way to skip discovery.
+    this._searchFixedTargets();
+
+    // Perform a UDP broadcast to search for SSDP devices
+    let socket = Cc["@mozilla.org/network/udp-socket;1"].createInstance(Ci.nsIUDPSocket);
+    try {
+      socket.init(SSDP_PORT, false);
+      socket.asyncListen(this);
+    } catch (e) {
+      // We were unable to create the broadcast socket. Just return, but don't
+      // kill the interval timer. This might work next time.
+      log("failed to start socket: " + e);
+      return;
+    }
+
+    this._searchSocket = socket;
+    this._searchTimeout.initWithCallback(this._searchShutdown.bind(this), SSDP_DISCOVER_TIMEOUT, Ci.nsITimer.TYPE_ONE_SHOT);
+
+    let data = SSDP_DISCOVER_PACKET;
+    for (let [key, target] of this._targets) {
+      let msgData = data.replace("%SEARCH_TARGET%", target.target);
+      try {
+        let msgRaw = converter.convertToByteArray(msgData);
+        socket.send(SSDP_ADDRESS, SSDP_PORT, msgRaw, msgRaw.length);
+      } catch (e) {
+        log("failed to convert to byte array: " + e);
+      }
+    }
+  },
+
+  _searchFixedTargets: function _searchFixedTargets() {
+    let fixedTargets = null;
+    try {
+      fixedTargets = Services.prefs.getCharPref("browser.casting.fixedTargets");
+    } catch (e) {}
+
+    if (!fixedTargets) {
+      return;
+    }
+
+    fixedTargets = JSON.parse(fixedTargets);
+    for (let fixedTarget of fixedTargets) {
+      // Verify we have the right data
+      if (!"location" in fixedTarget || !"target" in fixedTarget) {
+        continue;
+      }
+
+      fixedTarget.location = this._forceTrailingSlash(fixedTarget.location);
+
+      let service = {
+        location: fixedTarget.location,
+        target: fixedTarget.target
+      };
+
+      // We don't assume the fixed target is ready. We still need to ping it.
+      try {
+        this._processService(service);
+      } catch (e) {}
+    }
+  },
+
+  // Called when the search timeout is hit. We use it to cleanup the socket and
+  // perform some post-processing on the services list.
+  _searchShutdown: function _searchShutdown() {
+    if (this._searchSocket) {
+      // This will call onStopListening.
+      this._searchSocket.close();
+
+      // Clean out any stale services
+      for (let [key, service] of this._services) {
+        if (service.lastPing != this._searchTimestamp) {
+          Services.obs.notifyObservers(null, "ssdp-service-lost", service.location);
+          this._services.delete(service.location);
+        }
+      }
+    }
+  },
+
+  registerTarget: function registerTarget(aTarget, aAppFactory) {
+    // Only add if we don't already know about this target
+    if (!this._targets.has(aTarget)) {
+      this._targets.set(aTarget, { target: aTarget, factory: aAppFactory });
+    }
+  },
+
+  findAppForService: function findAppForService(aService, aApp) {
+    if (!aService || !aService.target) {
+      return null;
+    }
+
+    // Find the registration for the target
+    if (this._targets.has(aService.target)) {
+      return this._targets.get(aService.target).factory(aService, aApp);
+    }
+    return null;
+  },
+
+  findServiceForLocation: function findServiceForLocation(aLocation) {
+    if (this._services.has(aLocation)) {
+      return this._services.get(aLocation);
+    }
+    return null;
+  },
+
+  // Returns an array copy of the active services
+  get services() {
+    let array = [];
+    for (let [key, service] of this._services) {
+      array.push(service);
+    }
+    return array;
+  },
+
+  _processService: function _processService(aService) {
+    // Use the REST api to request more information about this service
+    let xhr = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"].createInstance(Ci.nsIXMLHttpRequest);
+    xhr.open("GET", aService.location, true);
+    xhr.channel.loadFlags |= Ci.nsIRequest.INHIBIT_CACHING;
+    xhr.overrideMimeType("text/xml");
+
+    xhr.addEventListener("load", (function() {
+      if (xhr.status == 200) {
+        let doc = xhr.responseXML;
+        aService.appsURL = xhr.getResponseHeader("Application-URL");
+        if (aService.appsURL && !aService.appsURL.endsWith("/"))
+          aService.appsURL += "/";
+        aService.friendlyName = doc.querySelector("friendlyName").textContent;
+        aService.uuid = doc.querySelector("UDN").textContent;
+        aService.manufacturer = doc.querySelector("manufacturer").textContent;
+        aService.modelName = doc.querySelector("modelName").textContent;
+
+        // Only add and notify if we don't already know about this service
+        if (!this._services.has(aService.location)) {
+          this._services.set(aService.location, aService);
+          Services.obs.notifyObservers(null, "ssdp-service-found", aService.location);
+        }
+
+        // Make sure we remember this service is not stale
+        this._services.get(aService.location).lastPing = this._searchTimestamp;
+      }
+    }).bind(this), false);
+
+    xhr.send(null);
+  }
+}