DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (5350524bb654)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
// 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/.

this.EXPORTED_SYMBOLS = ["RemoteAddonsParent"];

const Ci = Components.interfaces;
const Cc = Components.classes;
const Cu = Components.utils;
const Cr = Components.results;

Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/RemoteWebProgress.jsm");
Cu.import('resource://gre/modules/Services.jsm');

XPCOMUtils.defineLazyModuleGetter(this, "BrowserUtils",
                                  "resource://gre/modules/BrowserUtils.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "NetUtil",
                                  "resource://gre/modules/NetUtil.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Prefetcher",
                                  "resource://gre/modules/Prefetcher.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "CompatWarning",
                                  "resource://gre/modules/CompatWarning.jsm");

Cu.permitCPOWsInScope(this);

// Similar to Python. Returns dict[key] if it exists. Otherwise,
// sets dict[key] to default_ and returns default_.
function setDefault(dict, key, default_)
{
  if (key in dict) {
    return dict[key];
  }
  dict[key] = default_;
  return default_;
}

// This code keeps track of a set of paths of the form [component_1,
// ..., component_n]. The components can be strings or booleans. The
// child is notified whenever a path is added or removed, and new
// children can request the current set of paths. The purpose is to
// keep track of all the observers and events that the child should
// monitor for the parent.
var NotificationTracker = {
  // _paths is a multi-level dictionary. Let's add paths [A, B] and
  // [A, C]. Then _paths will look like this:
  //   { 'A': { 'B': { '_count': 1 }, 'C': { '_count': 1 } } }
  // Each component in a path will be a key in some dictionary. At the
  // end, the _count property keeps track of how many instances of the
  // given path are present in _paths.
  _paths: {},

  init: function() {
    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
               .getService(Ci.nsIMessageBroadcaster);
    ppmm.initialProcessData.remoteAddonsNotificationPaths = this._paths;
  },

  add: function(path) {
    let tracked = this._paths;
    for (let component of path) {
      tracked = setDefault(tracked, component, {});
    }
    let count = tracked._count || 0;
    count++;
    tracked._count = count;

    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
               .getService(Ci.nsIMessageBroadcaster);
    ppmm.broadcastAsyncMessage("Addons:ChangeNotification", {path: path, count: count});
  },

  remove: function(path) {
    let tracked = this._paths;
    for (let component of path) {
      tracked = setDefault(tracked, component, {});
    }
    tracked._count--;

    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
               .getService(Ci.nsIMessageBroadcaster);
    ppmm.broadcastAsyncMessage("Addons:ChangeNotification", {path: path, count: tracked._count});
  },
};
NotificationTracker.init();

// An interposition is an object with three properties: methods,
// getters, and setters. See multiprocessShims.js for an explanation
// of how these are used. The constructor here just allows one
// interposition to inherit members from another.
function Interposition(name, base)
{
  this.name = name;
  if (base) {
    this.methods = Object.create(base.methods);
    this.getters = Object.create(base.getters);
    this.setters = Object.create(base.setters);
  } else {
    this.methods = Object.create(null);
    this.getters = Object.create(null);
    this.setters = Object.create(null);
  }
}

// This object is responsible for notifying the child when a new
// content policy is added or removed. It also runs all the registered
// add-on content policies when the child asks it to do so.
var ContentPolicyParent = {
  init: function() {
    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
               .getService(Ci.nsIMessageBroadcaster);
    ppmm.addMessageListener("Addons:ContentPolicy:Run", this);

    this._policies = new Map();
  },

  addContentPolicy: function(addon, name, cid) {
    this._policies.set(name, cid);
    NotificationTracker.add(["content-policy", addon]);
  },

  removeContentPolicy: function(addon, name) {
    this._policies.delete(name);
    NotificationTracker.remove(["content-policy", addon]);
  },

  receiveMessage: function (aMessage) {
    switch (aMessage.name) {
      case "Addons:ContentPolicy:Run":
        return this.shouldLoad(aMessage.data, aMessage.objects);
    }
    return undefined;
  },

  shouldLoad: function(aData, aObjects) {
    for (let policyCID of this._policies.values()) {
      let policy;
      try {
        policy = Cc[policyCID].getService(Ci.nsIContentPolicy);
      } catch (e) {
        // Current Gecko behavior is to ignore entries that don't QI.
        continue;
      }
      try {
        let contentLocation = BrowserUtils.makeURI(aData.contentLocation);
        let requestOrigin = aData.requestOrigin ? BrowserUtils.makeURI(aData.requestOrigin) : null;

        let result = Prefetcher.withPrefetching(aData.prefetched, aObjects, () => {
          return policy.shouldLoad(aData.contentType,
                                   contentLocation,
                                   requestOrigin,
                                   aObjects.node,
                                   aData.mimeTypeGuess,
                                   null,
                                   aData.requestPrincipal);
        });
        if (result != Ci.nsIContentPolicy.ACCEPT && result != 0)
          return result;
      } catch (e) {
        Cu.reportError(e);
      }
    }

    return Ci.nsIContentPolicy.ACCEPT;
  },
};
ContentPolicyParent.init();

// This interposition intercepts calls to add or remove new content
// policies and forwards these requests to ContentPolicyParent.
var CategoryManagerInterposition = new Interposition("CategoryManagerInterposition");

CategoryManagerInterposition.methods.addCategoryEntry =
  function(addon, target, category, entry, value, persist, replace) {
    if (category == "content-policy") {
      CompatWarning.warn("content-policy should be added from the child process only.",
                         addon, CompatWarning.warnings.nsIContentPolicy);
      ContentPolicyParent.addContentPolicy(addon, entry, value);
    }

    target.addCategoryEntry(category, entry, value, persist, replace);
  };

CategoryManagerInterposition.methods.deleteCategoryEntry =
  function(addon, target, category, entry, persist) {
    if (category == "content-policy") {
      CompatWarning.warn("content-policy should be removed from the child process only.",
                         addon, CompatWarning.warnings.nsIContentPolicy);
      ContentPolicyParent.removeContentPolicy(addon, entry);
    }

    target.deleteCategoryEntry(category, entry, persist);
  };

// This shim handles the case where an add-on registers an about:
// protocol handler in the parent and we want the child to be able to
// use it. This code is pretty specific to Adblock's usage.
var AboutProtocolParent = {
  init: function() {
    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
               .getService(Ci.nsIMessageBroadcaster);
    ppmm.addMessageListener("Addons:AboutProtocol:GetURIFlags", this);
    ppmm.addMessageListener("Addons:AboutProtocol:OpenChannel", this);
    this._protocols = [];
  },

  registerFactory: function(addon, class_, className, contractID, factory) {
    this._protocols.push({contractID: contractID, factory: factory});
    NotificationTracker.add(["about-protocol", contractID, addon]);
  },

  unregisterFactory: function(addon, class_, factory) {
    for (let i = 0; i < this._protocols.length; i++) {
      if (this._protocols[i].factory == factory) {
        NotificationTracker.remove(["about-protocol", this._protocols[i].contractID, addon]);
        this._protocols.splice(i, 1);
        break;
      }
    }
  },

  receiveMessage: function (msg) {
    switch (msg.name) {
      case "Addons:AboutProtocol:GetURIFlags":
        return this.getURIFlags(msg);
      case "Addons:AboutProtocol:OpenChannel":
        return this.openChannel(msg);
    }
    return undefined;
  },

  getURIFlags: function(msg) {
    let uri = BrowserUtils.makeURI(msg.data.uri);
    let contractID = msg.data.contractID;
    let module = Cc[contractID].getService(Ci.nsIAboutModule);
    try {
      return module.getURIFlags(uri);
    } catch (e) {
      Cu.reportError(e);
      return undefined;
    }
  },

  // We immediately read all the data out of the channel here and
  // return it to the child.
  openChannel: function(msg) {
    function wrapGetInterface(cpow) {
      return {
        getInterface: function(intf) { return cpow.getInterface(intf); }
      };
    }

    let uri = BrowserUtils.makeURI(msg.data.uri);
    let channelParams;
    if (msg.data.contentPolicyType === Ci.nsIContentPolicy.TYPE_DOCUMENT) {
      // For TYPE_DOCUMENT loads, we cannot recreate the loadinfo here in the
      // parent. In that case, treat this as a chrome (addon)-requested
      // subload. When we use the data in the child, we'll load it into the
      // correctly-principaled document.
      channelParams = {
        uri,
        contractID: msg.data.contractID,
        loadingPrincipal: Services.scriptSecurityManager.getSystemPrincipal(),
        securityFlags: Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_DATA_IS_NULL,
        contentPolicyType: Ci.nsIContentPolicy.TYPE_OTHER
      };
    } else {
      // We can recreate the loadinfo here in the parent for non TYPE_DOCUMENT
      // loads.
      channelParams = {
        uri,
        contractID: msg.data.contractID,
        loadingPrincipal: msg.data.loadingPrincipal,
        securityFlags: msg.data.securityFlags,
        contentPolicyType: msg.data.contentPolicyType
      };
    }

    try {
      let channel = NetUtil.newChannel(channelParams);

      // We're not allowed to set channel.notificationCallbacks to a
      // CPOW, since the setter for notificationCallbacks is in C++,
      // which can't tolerate CPOWs. Instead we just use a JS object
      // that wraps the CPOW.
      channel.notificationCallbacks = wrapGetInterface(msg.objects.notificationCallbacks);
      if (msg.objects.loadGroupNotificationCallbacks) {
        channel.loadGroup = {notificationCallbacks: msg.objects.loadGroupNotificationCallbacks};
      } else {
        channel.loadGroup = null;
      }
      let stream = channel.open2();
      let data = NetUtil.readInputStreamToString(stream, stream.available(), {});
      return {
        data: data,
        contentType: channel.contentType
      };
    } catch (e) {
      Cu.reportError(e);
      return undefined;
    }
  },
};
AboutProtocolParent.init();

var ComponentRegistrarInterposition = new Interposition("ComponentRegistrarInterposition");

ComponentRegistrarInterposition.methods.registerFactory =
  function(addon, target, class_, className, contractID, factory) {
    if (contractID && contractID.startsWith("@mozilla.org/network/protocol/about;1?")) {
      CompatWarning.warn("nsIAboutModule should be registered in the content process" +
                         " as well as the chrome process. (If you do that already, ignore" +
                         " this warning.)",
                         addon, CompatWarning.warnings.nsIAboutModule);
      AboutProtocolParent.registerFactory(addon, class_, className, contractID, factory);
    }

    target.registerFactory(class_, className, contractID, factory);
  };

ComponentRegistrarInterposition.methods.unregisterFactory =
  function(addon, target, class_, factory) {
    AboutProtocolParent.unregisterFactory(addon, class_, factory);
    target.unregisterFactory(class_, factory);
  };

// This object manages add-on observers that might fire in the child
// process. Rather than managing the observers itself, it uses the
// parent's observer service. When an add-on listens on topic T,
// ObserverParent asks the child process to listen on T. It also adds
// an observer in the parent for the topic e10s-T. When the T observer
// fires in the child, the parent fires all the e10s-T observers,
// passing them CPOWs for the subject and data. We don't want to use T
// in the parent because there might be non-add-on T observers that
// won't expect to get notified in this case.
var ObserverParent = {
  init: function() {
    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
               .getService(Ci.nsIMessageBroadcaster);
    ppmm.addMessageListener("Addons:Observer:Run", this);
  },

  addObserver: function(addon, observer, topic, ownsWeak) {
    Services.obs.addObserver(observer, "e10s-" + topic, ownsWeak);
    NotificationTracker.add(["observer", topic, addon]);
  },

  removeObserver: function(addon, observer, topic) {
    Services.obs.removeObserver(observer, "e10s-" + topic);
    NotificationTracker.remove(["observer", topic, addon]);
  },

  receiveMessage: function(msg) {
    switch (msg.name) {
      case "Addons:Observer:Run":
        this.notify(msg.objects.subject, msg.objects.topic, msg.objects.data);
        break;
    }
  },

  notify: function(subject, topic, data) {
    let e = Services.obs.enumerateObservers("e10s-" + topic);
    while (e.hasMoreElements()) {
      let obs = e.getNext().QueryInterface(Ci.nsIObserver);
      try {
        obs.observe(subject, topic, data);
      } catch (e) {
        Cu.reportError(e);
      }
    }
  }
};
ObserverParent.init();

// We only forward observers for these topics.
var TOPIC_WHITELIST = [
  "content-document-global-created",
  "document-element-inserted",
  "dom-window-destroyed",
  "inner-window-destroyed",
  "outer-window-destroyed",
  "csp-on-violate-policy",
];

// This interposition listens for
// nsIObserverService.{add,remove}Observer.
var ObserverInterposition = new Interposition("ObserverInterposition");

ObserverInterposition.methods.addObserver =
  function(addon, target, observer, topic, ownsWeak) {
    if (TOPIC_WHITELIST.indexOf(topic) >= 0) {
      CompatWarning.warn(`${topic} observer should be added from the child process only.`,
                         addon, CompatWarning.warnings.observers);

      ObserverParent.addObserver(addon, observer, topic);
    }

    target.addObserver(observer, topic, ownsWeak);
  };

ObserverInterposition.methods.removeObserver =
  function(addon, target, observer, topic) {
    if (TOPIC_WHITELIST.indexOf(topic) >= 0) {
      ObserverParent.removeObserver(addon, observer, topic);
    }

    target.removeObserver(observer, topic);
  };

// This object is responsible for forwarding events from the child to
// the parent.
var EventTargetParent = {
  init: function() {
    // The _listeners map goes from targets (either <browser> elements
    // or windows) to a dictionary from event types to listeners.
    this._listeners = new WeakMap();

    let mm = Cc["@mozilla.org/globalmessagemanager;1"].
      getService(Ci.nsIMessageListenerManager);
    mm.addMessageListener("Addons:Event:Run", this);
  },

  // If target is not on the path from a <browser> element to the
  // window root, then we return null here to ignore the
  // target. Otherwise, if the target is a browser-specific element
  // (the <browser> or <tab> elements), then we return the
  // <browser>. If it's some generic element, then we return the
  // window itself.
  redirectEventTarget: function(target) {
    if (Cu.isCrossProcessWrapper(target)) {
      return null;
    }

    if (target instanceof Ci.nsIDOMChromeWindow) {
      return target;
    }

    if (target instanceof Ci.nsIDOMXULElement) {
      if (target.localName == "browser") {
        return target;
      } else if (target.localName == "tab") {
        return target.linkedBrowser;
      }

      // Check if |target| is somewhere on the patch from the
      // <tabbrowser> up to the root element.
      let window = target.ownerDocument.defaultView;
      if (window && target.contains(window.gBrowser)) {
        return window;
      }
    }

    return null;
  },

  // When a given event fires in the child, we fire it on the
  // <browser> element and the window since those are the two possible
  // results of redirectEventTarget.
  getTargets: function(browser) {
    let window = browser.ownerDocument.defaultView;
    return [browser, window];
  },

  addEventListener: function(addon, target, type, listener, useCapture, wantsUntrusted, delayedWarning) {
    let newTarget = this.redirectEventTarget(target);
    if (!newTarget) {
      return;
    }

    useCapture = useCapture || false;
    wantsUntrusted = wantsUntrusted || false;

    NotificationTracker.add(["event", type, useCapture, addon]);

    let listeners = this._listeners.get(newTarget);
    if (!listeners) {
      listeners = {};
      this._listeners.set(newTarget, listeners);
    }
    let forType = setDefault(listeners, type, []);

    // If there's already an identical listener, don't do anything.
    for (let i = 0; i < forType.length; i++) {
      if (forType[i].listener === listener &&
          forType[i].target === target &&
          forType[i].useCapture === useCapture &&
          forType[i].wantsUntrusted === wantsUntrusted) {
        return;
      }
    }

    forType.push({listener: listener,
                  target: target,
                  wantsUntrusted: wantsUntrusted,
                  useCapture: useCapture,
                  delayedWarning: delayedWarning});
  },

  removeEventListener: function(addon, target, type, listener, useCapture) {
    let newTarget = this.redirectEventTarget(target);
    if (!newTarget) {
      return;
    }

    useCapture = useCapture || false;

    let listeners = this._listeners.get(newTarget);
    if (!listeners) {
      return;
    }
    let forType = setDefault(listeners, type, []);

    for (let i = 0; i < forType.length; i++) {
      if (forType[i].listener === listener &&
          forType[i].target === target &&
          forType[i].useCapture === useCapture) {
        forType.splice(i, 1);
        NotificationTracker.remove(["event", type, useCapture, addon]);
        break;
      }
    }
  },

  receiveMessage: function(msg) {
    switch (msg.name) {
      case "Addons:Event:Run":
        this.dispatch(msg.target, msg.data.type, msg.data.capturing,
                      msg.data.isTrusted, msg.data.prefetched, msg.objects);
        break;
    }
  },

  dispatch: function(browser, type, capturing, isTrusted, prefetched, cpows) {
    let event = cpows.event;
    let eventTarget = cpows.eventTarget;
    let targets = this.getTargets(browser);
    for (let target of targets) {
      let listeners = this._listeners.get(target);
      if (!listeners) {
        continue;
      }
      let forType = setDefault(listeners, type, []);

      // Make a copy in case they call removeEventListener in the listener.
      let handlers = [];
      for (let {listener, target, wantsUntrusted, useCapture, delayedWarning} of forType) {
        if ((wantsUntrusted || isTrusted) && useCapture == capturing) {
          // Issue a warning for this listener.
          delayedWarning();

          handlers.push([listener, target]);
        }
      }

      for (let [handler, target] of handlers) {
        let EventProxy = {
          get: function(knownProps, name) {
            if (knownProps.hasOwnProperty(name))
              return knownProps[name];
            return event[name];
          }
        }
        let proxyEvent = new Proxy({
          currentTarget: target,
          target: eventTarget,
          type: type,
          QueryInterface: function(iid) {
            if (iid.equals(Ci.nsISupports) ||
                iid.equals(Ci.nsIDOMEventTarget))
              return proxyEvent;
            // If event deson't support the interface this will throw. If it
            // does we want to return the proxy
            event.QueryInterface(iid);
            return proxyEvent;
          }
        }, EventProxy);

        try {
          Prefetcher.withPrefetching(prefetched, cpows, () => {
            if ("handleEvent" in handler) {
              handler.handleEvent(proxyEvent);
            } else {
              handler.call(eventTarget, proxyEvent);
            }
          });
        } catch (e) {
          Cu.reportError(e);
        }
      }
    }
  }
};
EventTargetParent.init();

// This function returns a listener that will not fire on events where
// the target is a remote xul:browser element itself. We'd rather let
// the child process handle the event and pass it up via
// EventTargetParent.
var filteringListeners = new WeakMap();
function makeFilteringListener(eventType, listener)
{
  // Some events are actually targeted at the <browser> element
  // itself, so we only handle the ones where know that won't happen.
  let eventTypes = ["mousedown", "mouseup", "click"];
  if (!eventTypes.includes(eventType) || !listener ||
      (typeof listener != "object" && typeof listener != "function")) {
    return listener;
  }

  if (filteringListeners.has(listener)) {
    return filteringListeners.get(listener);
  }

  function filter(event) {
    let target = event.originalTarget;
    if (target instanceof Ci.nsIDOMXULElement &&
        target.localName == "browser" &&
        target.isRemoteBrowser) {
      return;
    }

    if ("handleEvent" in listener) {
      listener.handleEvent(event);
    } else {
      listener.call(event.target, event);
    }
  }
  filteringListeners.set(listener, filter);
  return filter;
}

// This interposition redirects addEventListener and
// removeEventListener to EventTargetParent.
var EventTargetInterposition = new Interposition("EventTargetInterposition");

EventTargetInterposition.methods.addEventListener =
  function(addon, target, type, listener, useCapture, wantsUntrusted) {
    let delayed = CompatWarning.delayedWarning(
      `Registering a ${type} event listener on content DOM nodes` +
        " needs to happen in the content process.",
      addon, CompatWarning.warnings.DOM_events);

    EventTargetParent.addEventListener(addon, target, type, listener, useCapture, wantsUntrusted, delayed);
    target.addEventListener(type, makeFilteringListener(type, listener), useCapture, wantsUntrusted);
  };

EventTargetInterposition.methods.removeEventListener =
  function(addon, target, type, listener, useCapture) {
    EventTargetParent.removeEventListener(addon, target, type, listener, useCapture);
    target.removeEventListener(type, makeFilteringListener(type, listener), useCapture);
  };

// This interposition intercepts accesses to |rootTreeItem| on a child
// process docshell. In the child, each docshell is its own
// root. However, add-ons expect the root to be the chrome docshell,
// so we make that happen here.
var ContentDocShellTreeItemInterposition = new Interposition("ContentDocShellTreeItemInterposition");

ContentDocShellTreeItemInterposition.getters.rootTreeItem =
  function(addon, target) {
    // The chrome global in the child.
    let chromeGlobal = target.rootTreeItem
      .QueryInterface(Ci.nsIInterfaceRequestor)
      .getInterface(Ci.nsIContentFrameMessageManager);

    // Map it to a <browser> element and window.
    let browser = RemoteAddonsParent.globalToBrowser.get(chromeGlobal);
    if (!browser) {
      // Somehow we have a CPOW from the child, but it hasn't sent us
      // its global yet. That shouldn't happen, but return null just
      // in case.
      return null;
    }

    let chromeWin = browser.ownerDocument.defaultView;

    // Return that window's docshell.
    return chromeWin.QueryInterface(Ci.nsIInterfaceRequestor)
      .getInterface(Ci.nsIWebNavigation)
      .QueryInterface(Ci.nsIDocShellTreeItem);
  };

function chromeGlobalForContentWindow(window)
{
    return window
      .QueryInterface(Ci.nsIInterfaceRequestor)
      .getInterface(Ci.nsIWebNavigation)
      .QueryInterface(Ci.nsIDocShellTreeItem)
      .rootTreeItem
      .QueryInterface(Ci.nsIInterfaceRequestor)
      .getInterface(Ci.nsIContentFrameMessageManager);
}

// This object manages sandboxes created with content principals in
// the parent. We actually create these sandboxes in the child process
// so that the code loaded into them runs there. The resulting sandbox
// object is a CPOW. This is primarly useful for Greasemonkey.
var SandboxParent = {
  componentsMap: new WeakMap(),

  makeContentSandbox: function(addon, chromeGlobal, principals, ...rest) {
    CompatWarning.warn("This sandbox should be created from the child process.",
                       addon, CompatWarning.warnings.sandboxes);
    if (rest.length) {
      // Do a shallow copy of the options object into the child
      // process. This way we don't have to access it through a Chrome
      // object wrapper, which would require __exposedProps__.
      //
      // The only object property here is sandboxPrototype. We assume
      // it's a child process object (since that's what Greasemonkey
      // does) and leave it alone.
      let options = rest[0];
      let optionsCopy = new chromeGlobal.Object();
      for (let prop in options) {
        optionsCopy[prop] = options[prop];
      }
      rest[0] = optionsCopy;
    }

    // Make a sandbox in the child.
    let cu = chromeGlobal.Components.utils;
    let sandbox = cu.Sandbox(principals, ...rest);

    // We need to save the sandbox in the child so it won't get
    // GCed. The child will drop this reference at the next
    // navigation.
    chromeGlobal.addSandbox(sandbox);

    // The sandbox CPOW will be kept alive by whomever we return it
    // to. Its lifetime is unrelated to that of the sandbox object in
    // the child.
    this.componentsMap.set(sandbox, cu);
    return sandbox;
  },

  evalInSandbox: function(code, sandbox, ...rest) {
    let cu = this.componentsMap.get(sandbox);
    return cu.evalInSandbox(code, sandbox, ...rest);
  }
};

// This interposition redirects calls to Cu.Sandbox and
// Cu.evalInSandbox to SandboxParent if the principals are content
// principals.
var ComponentsUtilsInterposition = new Interposition("ComponentsUtilsInterposition");

ComponentsUtilsInterposition.methods.Sandbox =
  function(addon, target, principals, ...rest) {
    // principals can be a window object, a list of window objects, or
    // something else (a string, for example).
    if (principals &&
        typeof(principals) == "object" &&
        Cu.isCrossProcessWrapper(principals) &&
        principals instanceof Ci.nsIDOMWindow) {
      let chromeGlobal = chromeGlobalForContentWindow(principals);
      return SandboxParent.makeContentSandbox(addon, chromeGlobal, principals, ...rest);
    } else if (principals &&
               typeof(principals) == "object" &&
               "every" in principals &&
               principals.length &&
               principals.every(e => e instanceof Ci.nsIDOMWindow && Cu.isCrossProcessWrapper(e))) {
      let chromeGlobal = chromeGlobalForContentWindow(principals[0]);

      // The principals we pass to the content process must use an
      // Array object from the content process.
      let array = new chromeGlobal.Array();
      for (let i = 0; i < principals.length; i++) {
        array[i] = principals[i];
      }
      return SandboxParent.makeContentSandbox(addon, chromeGlobal, array, ...rest);
    }
    return Components.utils.Sandbox(principals, ...rest);
  };

ComponentsUtilsInterposition.methods.evalInSandbox =
  function(addon, target, code, sandbox, ...rest) {
    if (sandbox && Cu.isCrossProcessWrapper(sandbox)) {
      return SandboxParent.evalInSandbox(code, sandbox, ...rest);
    }
    return Components.utils.evalInSandbox(code, sandbox, ...rest);
  };

// This interposition handles cases where an add-on tries to import a
// chrome XUL node into a content document. It doesn't actually do the
// import, which we can't support. It just avoids throwing an
// exception.
var ContentDocumentInterposition = new Interposition("ContentDocumentInterposition");

ContentDocumentInterposition.methods.importNode =
  function(addon, target, node, deep) {
    if (!Cu.isCrossProcessWrapper(node)) {
      // Trying to import a node from the parent process into the
      // child process. We don't support this now. Video Download
      // Helper does this in domhook-service.js to add a XUL
      // popupmenu to content.
      Cu.