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.

Implementation

Mercurial (c68fe15a81fc)

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
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */

#ifndef mozilla_dom_BrowsingContext_h
#define mozilla_dom_BrowsingContext_h

#include "GVAutoplayRequestUtils.h"
#include "mozilla/HalScreenConfiguration.h"
#include "mozilla/LinkedList.h"
#include "mozilla/Maybe.h"
#include "mozilla/RefPtr.h"
#include "mozilla/Span.h"
#include "mozilla/Tuple.h"
#include "mozilla/WeakPtr.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/LoadURIOptionsBinding.h"
#include "mozilla/dom/LocationBase.h"
#include "mozilla/dom/MaybeDiscarded.h"
#include "mozilla/dom/FeaturePolicyUtils.h"
#include "mozilla/dom/SessionStorageManager.h"
#include "mozilla/dom/UserActivation.h"
#include "mozilla/dom/SyncedContext.h"
#include "nsCOMPtr.h"
#include "nsCycleCollectionParticipant.h"
#include "nsID.h"
#include "nsIDocShell.h"
#include "nsString.h"
#include "nsTArray.h"
#include "nsWrapperCache.h"
#include "nsILoadInfo.h"
#include "nsILoadContext.h"

class nsDocShellLoadState;
class nsGlobalWindowInner;
class nsGlobalWindowOuter;
class nsILoadInfo;
class nsIPrincipal;
class nsOuterWindowProxy;
class PickleIterator;

namespace IPC {
class Message;
}  // namespace IPC

namespace mozilla {

class ErrorResult;
class LogModule;

namespace ipc {
class IProtocol;

template <typename T>
struct IPDLParamTraits;
}  // namespace ipc

namespace dom {
class BrowsingContent;
class BrowsingContextGroup;
class CanonicalBrowsingContext;
class ChildSHistory;
class ContentParent;
class Element;
template <typename>
struct Nullable;
template <typename T>
class Sequence;
class StructuredCloneHolder;
class WindowContext;
struct WindowPostMessageOptions;
class WindowProxyHolder;

// Fields are, by default, settable by any process and readable by any process.
// Racy sets will be resolved as-if they occurred in the order the parent
// process finds out about them.
//
// The `DidSet` and `CanSet` methods may be overloaded to provide different
// behavior for a specific field.
//  * `DidSet` is called to run code in every process whenever the value is
//    updated (This currently occurs even if the value didn't change, though
//    this may change in the future).
//  * `CanSet` is called before attempting to set the value, in both the process
//    which calls `Set`, and the parent process, and will kill the misbehaving
//    process if it fails.
#define MOZ_EACH_BC_FIELD(FIELD)                                             \
  FIELD(Name, nsString)                                                      \
  FIELD(Closed, bool)                                                        \
  FIELD(IsActive, bool)                                                      \
  FIELD(OpenerPolicy, nsILoadInfo::CrossOriginOpenerPolicy)                  \
  /* Current opener for the BrowsingContext. Weak reference */               \
  FIELD(OpenerId, uint64_t)                                                  \
  FIELD(OnePermittedSandboxedNavigatorId, uint64_t)                          \
  /* WindowID of the inner window which embeds this BC */                    \
  FIELD(EmbedderInnerWindowId, uint64_t)                                     \
  FIELD(CurrentInnerWindowId, uint64_t)                                      \
  FIELD(HadOriginalOpener, bool)                                             \
  FIELD(IsPopupSpam, bool)                                                   \
  /* Controls whether the BrowsingContext is currently considered to be      \
   * activated by a gesture */                                               \
  FIELD(UserActivationState, UserActivation::State)                          \
  /* Hold the audio muted state and should be used on top level browsing     \
   * contexts only */                                                        \
  FIELD(Muted, bool)                                                         \
  FIELD(FeaturePolicy, RefPtr<mozilla::dom::FeaturePolicy>)                  \
  /* See nsSandboxFlags.h for the possible flags. */                         \
  FIELD(SandboxFlags, uint32_t)                                              \
  FIELD(HistoryID, nsID)                                                     \
  FIELD(InRDMPane, bool)                                                     \
  FIELD(Loading, bool)                                                       \
  FIELD(AncestorLoading, bool)                                               \
  FIELD(AllowPlugins, bool)                                                  \
  FIELD(AllowContentRetargeting, bool)                                       \
  FIELD(AllowContentRetargetingOnChildren, bool)                             \
  FIELD(ForceEnableTrackingProtection, bool)                                 \
  FIELD(UseGlobalHistory, bool)                                              \
  FIELD(FullscreenAllowedByOwner, bool)                                      \
  /* These field are used to store the states of autoplay media request on   \
   * GeckoView only, and it would only be modified on the top level browsing \
   * context. */                                                             \
  FIELD(GVAudibleAutoplayRequestStatus, GVAutoplayRequestStatus)             \
  FIELD(GVInaudibleAutoplayRequestStatus, GVAutoplayRequestStatus)           \
  /* ScreenOrientation-related APIs */                                       \
  FIELD(CurrentOrientationAngle, float)                                      \
  FIELD(CurrentOrientationType, mozilla::dom::OrientationType)               \
  FIELD(OrientationLock, mozilla::hal::ScreenOrientation)                    \
  FIELD(UserAgentOverride, nsString)                                         \
  FIELD(EmbedderElementType, Maybe<nsString>)                                \
  FIELD(MessageManagerGroup, nsString)                                       \
  FIELD(MaxTouchPointsOverride, uint8_t)                                     \
  FIELD(FullZoom, float)                                                     \
  FIELD(WatchedByDevToolsInternal, bool)                                     \
  FIELD(TextZoom, float)                                                     \
  /* See nsIRequest for possible flags. */                                   \
  FIELD(DefaultLoadFlags, uint32_t)                                          \
  /* Signals that session history is enabled for this browsing context tree. \
   * This is only ever set to true on the top BC, so consumers need to get   \
   * the value from the top BC! */                                           \
  FIELD(HasSessionHistory, bool)

// BrowsingContext, in this context, is the cross process replicated
// environment in which information about documents is stored. In
// particular the tree structure of nested browsing contexts is
// represented by the tree of BrowsingContexts.
//
// The tree of BrowsingContexts is created in step with its
// corresponding nsDocShell, and when nsDocShells are connected
// through a parent/child relationship, so are BrowsingContexts. The
// major difference is that BrowsingContexts are replicated (synced)
// to the parent process, making it possible to traverse the
// BrowsingContext tree for a tab, in both the parent and the child
// process.
//
// Trees of BrowsingContexts should only ever contain nodes of the
// same BrowsingContext::Type. This is enforced by asserts in the
// BrowsingContext::Create* methods.
class BrowsingContext : public nsILoadContext, public nsWrapperCache {
  MOZ_DECL_SYNCED_CONTEXT(BrowsingContext, MOZ_EACH_BC_FIELD)

 public:
  enum class Type { Chrome, Content };

  static void Init();
  static LogModule* GetLog();
  static void CleanupContexts(uint64_t aProcessId);

  // Look up a BrowsingContext in the current process by ID.
  static already_AddRefed<BrowsingContext> Get(uint64_t aId);
  static already_AddRefed<BrowsingContext> Get(GlobalObject&, uint64_t aId) {
    return Get(aId);
  }

  static already_AddRefed<BrowsingContext> GetFromWindow(
      WindowProxyHolder& aProxy);
  static already_AddRefed<BrowsingContext> GetFromWindow(
      GlobalObject&, WindowProxyHolder& aProxy) {
    return GetFromWindow(aProxy);
  }

  // Create a brand-new toplevel BrowsingContext with no relationships to other
  // BrowsingContexts, and which is not embedded within any <browser> or frame
  // element.
  //
  // This BrowsingContext is immediately attached, and cannot have LoadContext
  // flags customized unless it is of `Type::Chrome`.
  //
  // The process which created this BrowsingContext is responsible for detaching
  // it.
  static already_AddRefed<BrowsingContext> CreateIndependent(Type aType);

  // Create a brand-new BrowsingContext object, but does not immediately attach
  // it. State such as OriginAttributes and PrivateBrowsingId may be customized
  // to configure the BrowsingContext before it is attached.
  //
  // `EnsureAttached()` must be called before the BrowsingContext is used for a
  // DocShell, BrowserParent, or BrowserBridgeChild.
  static already_AddRefed<BrowsingContext> CreateDetached(
      nsGlobalWindowInner* aParent, BrowsingContext* aOpener,
      const nsAString& aName, Type aType);

  void EnsureAttached();

  bool EverAttached() const { return mEverAttached; }

  // Cast this object to a canonical browsing context, and return it.
  CanonicalBrowsingContext* Canonical();

  // Is the most recent Document in this BrowsingContext loaded within this
  // process? This may be true with a null mDocShell after the Window has been
  // closed.
  bool IsInProcess() const { return mIsInProcess; }

  bool CanHaveRemoteOuterProxies() const {
    return !mIsInProcess || mDanglingRemoteOuterProxies;
  }

  // Has this BrowsingContext been discarded. A discarded browsing context has
  // been destroyed, and may not be available on the other side of an IPC
  // message.
  bool IsDiscarded() const { return mIsDiscarded; }

  bool Windowless() const { return mWindowless; }

  // Get the DocShell for this BrowsingContext if it is in-process, or
  // null if it's not.
  nsIDocShell* GetDocShell() const { return mDocShell; }
  void SetDocShell(nsIDocShell* aDocShell);
  void ClearDocShell() { mDocShell = nullptr; }

  // Get the Document for this BrowsingContext if it is in-process, or
  // null if it's not.
  Document* GetDocument() const {
    return mDocShell ? mDocShell->GetDocument() : nullptr;
  }

  // This cleans up remote outer window proxies that might have been left behind
  // when the browsing context went from being remote to local. It does this by
  // turning them into cross-compartment wrappers to aOuter. If there is already
  // a remote proxy in the compartment of aOuter, then aOuter will get swapped
  // to it and the value of aOuter will be set to the object that used to be the
  // remote proxy and is now an OuterWindowProxy.
  void CleanUpDanglingRemoteOuterWindowProxies(
      JSContext* aCx, JS::MutableHandle<JSObject*> aOuter);

  // Get the embedder element for this BrowsingContext if the embedder is
  // in-process, or null if it's not.
  Element* GetEmbedderElement() const { return mEmbedderElement; }
  void SetEmbedderElement(Element* aEmbedder);

  // Called after the BrowingContext has been embedded in a FrameLoader. This
  // happens after `SetEmbedderElement` is called on the BrowsingContext and
  // after the BrowsingContext has been set on the FrameLoader.
  void Embed();

  // Get the outer window object for this BrowsingContext if it is in-process
  // and still has a docshell, or null otherwise.
  nsPIDOMWindowOuter* GetDOMWindow() const {
    return mDocShell ? mDocShell->GetWindow() : nullptr;
  }

  uint64_t GetRequestContextId() const { return mRequestContextId; }

  // Detach the current BrowsingContext from its parent, in both the
  // child and the parent process.
  void Detach(bool aFromIPC = false);

  // Prepare this BrowsingContext to leave the current process.
  void PrepareForProcessChange();

  // Triggers a load in the process which currently owns this BrowsingContext.
  nsresult LoadURI(nsDocShellLoadState* aLoadState,
                   bool aSetNavigating = false);

  nsresult InternalLoad(nsDocShellLoadState* aLoadState,
                        nsIDocShell** aDocShell, nsIRequest** aRequest);

  // If the load state includes a source BrowsingContext has been passed, check
  // to see if we are sandboxed from it as the result of an iframe or CSP
  // sandbox.
  nsresult CheckSandboxFlags(nsDocShellLoadState* aLoadState);

  void DisplayLoadError(const nsAString& aURI);

  // Determine if the current BrowsingContext is in the BFCache.
  bool IsCached();

  // Check that this browsing context is targetable for navigations (i.e. that
  // it is neither closed, cached, nor discarded).
  bool IsTargetable();

  const nsString& Name() const { return GetName(); }
  void GetName(nsAString& aName) { aName = GetName(); }
  bool NameEquals(const nsAString& aName) { return GetName().Equals(aName); }

  Type GetType() const { return mType; }
  bool IsContent() const { return mType == Type::Content; }
  bool IsChrome() const { return !IsContent(); }

  bool IsTop() const { return !GetParent(); }

  bool IsTopContent() const { return IsContent() && !GetParent(); }

  bool IsInSubtreeOf(BrowsingContext* aContext);

  bool IsContentSubframe() const { return IsContent() && GetParent(); }
  uint64_t Id() const { return mBrowsingContextId; }

  BrowsingContext* GetParent() const;
  BrowsingContext* Top();

  // NOTE: Unlike `GetEmbedderWindowGlobal`, `GetParentWindowContext` does not
  // cross toplevel content browser boundaries.
  WindowContext* GetParentWindowContext() const { return mParentWindow; }
  WindowContext* GetTopWindowContext();

  already_AddRefed<BrowsingContext> GetOpener() const {
    RefPtr<BrowsingContext> opener(Get(GetOpenerId()));
    if (!mIsDiscarded && opener && !opener->mIsDiscarded) {
      MOZ_DIAGNOSTIC_ASSERT(opener->mType == mType);
      return opener.forget();
    }
    return nullptr;
  }
  void SetOpener(BrowsingContext* aOpener) {
    MOZ_DIAGNOSTIC_ASSERT(!aOpener || aOpener->Group() == Group());
    MOZ_DIAGNOSTIC_ASSERT(!aOpener || aOpener->mType == mType);
    SetOpenerId(aOpener ? aOpener->Id() : 0);
  }

  bool HasOpener() const;

  bool HadOriginalOpener() const { return GetHadOriginalOpener(); }

  // Returns true if the browsing context and top context are same origin
  bool SameOriginWithTop();

  /**
   * When a new browsing context is opened by a sandboxed document, it needs to
   * keep track of the browsing context that opened it, so that it can be
   * navigated by it.  This is the "one permitted sandboxed navigator".
   */
  already_AddRefed<BrowsingContext> GetOnePermittedSandboxedNavigator() const {
    return Get(GetOnePermittedSandboxedNavigatorId());
  }
  void SetOnePermittedSandboxedNavigator(BrowsingContext* aNavigator) {
    if (GetOnePermittedSandboxedNavigatorId()) {
      MOZ_ASSERT(false,
                 "One Permitted Sandboxed Navigator should only be set once.");
    } else {
      SetOnePermittedSandboxedNavigatorId(aNavigator ? aNavigator->Id() : 0);
    }
  }

  uint32_t SandboxFlags() { return GetSandboxFlags(); }

  Span<RefPtr<BrowsingContext>> Children() const;
  void GetChildren(nsTArray<RefPtr<BrowsingContext>>& aChildren);

  const nsTArray<RefPtr<WindowContext>>& GetWindowContexts() {
    return mWindowContexts;
  }
  void GetWindowContexts(nsTArray<RefPtr<WindowContext>>& aWindows);

  void RegisterWindowContext(WindowContext* aWindow);
  void UnregisterWindowContext(WindowContext* aWindow);
  WindowContext* GetCurrentWindowContext() const {
    return mCurrentWindowContext;
  }

  BrowsingContextGroup* Group() { return mGroup; }

  // WebIDL bindings for nsILoadContext
  Nullable<WindowProxyHolder> GetAssociatedWindow();
  Nullable<WindowProxyHolder> GetTopWindow();
  Element* GetTopFrameElement();
  bool GetIsContent() { return IsContent(); }
  void SetUsePrivateBrowsing(bool aUsePrivateBrowsing, ErrorResult& aError);
  // Needs a different name to disambiguate from the xpidl method with
  // the same signature but different return value.
  void SetUseTrackingProtectionWebIDL(bool aUseTrackingProtection);
  bool UseTrackingProtectionWebIDL() { return UseTrackingProtection(); }
  void GetOriginAttributes(JSContext* aCx, JS::MutableHandle<JS::Value> aVal,
                           ErrorResult& aError);

  bool InRDMPane() const { return GetInRDMPane(); }

  bool WatchedByDevTools();
  void SetWatchedByDevTools(bool aWatchedByDevTools, ErrorResult& aRv);

  bool FullscreenAllowed() const;

  float FullZoom() const { return GetFullZoom(); }
  float TextZoom() const { return GetTextZoom(); }

  bool UseGlobalHistory() const { return GetUseGlobalHistory(); }

  bool IsLoading();

  // ScreenOrientation related APIs
  void SetCurrentOrientation(OrientationType aType, float aAngle) {
    SetCurrentOrientationType(aType);
    SetCurrentOrientationAngle(aAngle);
  }

  void SetRDMPaneOrientation(OrientationType aType, float aAngle) {
    if (InRDMPane()) {
      SetCurrentOrientation(aType, aAngle);
    }
  }

  void SetRDMPaneMaxTouchPoints(uint8_t aMaxTouchPoints) {
    if (InRDMPane()) {
      SetMaxTouchPointsOverride(aMaxTouchPoints);
    }
  }

  void SetAllowContentRetargeting(bool aAllowContentRetargeting);

  // Using the rules for choosing a browsing context we try to find
  // the browsing context with the given name in the set of
  // transitively reachable browsing contexts. Performs access control
  // checks with regard to this.
  // See
  // https://html.spec.whatwg.org/multipage/browsers.html#the-rules-for-choosing-a-browsing-context-given-a-browsing-context-name.
  //
  // BrowsingContext::FindWithName(const nsAString&) is equivalent to
  // calling nsIDocShellTreeItem::FindItemWithName(aName, nullptr,
  // nullptr, false, <return value>).
  BrowsingContext* FindWithName(const nsAString& aName,
                                bool aUseEntryGlobalForAccessCheck = true);

  // Find a browsing context in this context's list of
  // children. Doesn't consider the special names, '_self', '_parent',
  // '_top', or '_blank'. Performs access control checks with regard to
  // 'this'.
  BrowsingContext* FindChildWithName(const nsAString& aName,
                                     BrowsingContext& aRequestingContext);

  // Find a browsing context in the subtree rooted at 'this' Doesn't
  // consider the special names, '_self', '_parent', '_top', or
  // '_blank'. Performs access control checks with regard to
  // 'aRequestingContext'.
  BrowsingContext* FindWithNameInSubtree(const nsAString& aName,
                                         BrowsingContext& aRequestingContext);

  nsISupports* GetParentObject() const;
  JSObject* WrapObject(JSContext* aCx,
                       JS::Handle<JSObject*> aGivenProto) override;

  // This function would be called when its corresponding document is activated
  // by user gesture, and we would set the flag in the top level browsing
  // context.
  void NotifyUserGestureActivation();

  // This function would be called when we want to reset the user gesture
  // activation flag of the top level browsing context.
  void NotifyResetUserGestureActivation();

  // Return true if its corresponding document has been activated by user
  // gesture.
  bool HasBeenUserGestureActivated();

  // Return true if its corresponding document has transient user gesture
  // activation and the transient user gesture activation haven't yet timed
  // out.
  bool HasValidTransientUserGestureActivation();

  // Return true if the corresponding document has valid transient user gesture
  // activation and the transient user gesture activation had been consumed
  // successfully.
  bool ConsumeTransientUserGestureActivation();

  // Return the window proxy object that corresponds to this browsing context.
  inline JSObject* GetWindowProxy() const { return mWindowProxy; }
  inline JSObject* GetUnbarrieredWindowProxy() const {
    return mWindowProxy.unbarrieredGet();
  }

  // Set the window proxy object that corresponds to this browsing context.
  void SetWindowProxy(JS::Handle<JSObject*> aWindowProxy) {
    mWindowProxy = aWindowProxy;
  }

  Nullable<WindowProxyHolder> GetWindow();

  MOZ_DECLARE_WEAKREFERENCE_TYPENAME(BrowsingContext)

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(BrowsingContext)
  NS_DECL_NSILOADCONTEXT

  // Perform a pre-order walk of this BrowsingContext subtree.
  void PreOrderWalk(const std::function<void(BrowsingContext*)>& aCallback) {
    aCallback(this);
    for (auto& child : Children()) {
      child->PreOrderWalk(aCallback);
    }
  }

  // Perform an post-order walk of this BrowsingContext subtree.
  void PostOrderWalk(const std::function<void(BrowsingContext*)>& aCallback) {
    for (auto& child : Children()) {
      child->PostOrderWalk(aCallback);
    }

    aCallback(this);
  }

  // Window APIs that are cross-origin-accessible (from the HTML spec).
  WindowProxyHolder Window();
  BrowsingContext* Self() { return this; }
  void Location(JSContext* aCx, JS::MutableHandle<JSObject*> aLocation,
                ErrorResult& aError);
  void Close(CallerType aCallerType, ErrorResult& aError);
  bool GetClosed(ErrorResult&) { return GetClosed(); }
  void Focus(CallerType aCallerType, ErrorResult& aError);
  void Blur(ErrorResult& aError);
  WindowProxyHolder GetFrames(ErrorResult& aError);
  int32_t Length() const { return Children().Length(); }
  Nullable<WindowProxyHolder> GetTop(ErrorResult& aError);
  void GetOpener(JSContext* aCx, JS::MutableHandle<JS::Value> aOpener,
                 ErrorResult& aError) const;
  Nullable<WindowProxyHolder> GetParent(ErrorResult& aError);
  void PostMessageMoz(JSContext* aCx, JS::Handle<JS::Value> aMessage,
                      const nsAString& aTargetOrigin,
                      const Sequence<JSObject*>& aTransfer,
                      nsIPrincipal& aSubjectPrincipal, ErrorResult& aError);
  void PostMessageMoz(JSContext* aCx, JS::Handle<JS::Value> aMessage,
                      const WindowPostMessageOptions& aOptions,
                      nsIPrincipal& aSubjectPrincipal, ErrorResult& aError);

  void GetCustomUserAgent(nsAString& aUserAgent) {
    aUserAgent = Top()->GetUserAgentOverride();
  }
  void SetCustomUserAgent(const nsAString& aUserAgent);

  JSObject* WrapObject(JSContext* aCx);

  static JSObject* ReadStructuredClone(JSContext* aCx,
                                       JSStructuredCloneReader* aReader,
                                       StructuredCloneHolder* aHolder);
  bool WriteStructuredClone(JSContext* aCx, JSStructuredCloneWriter* aWriter,
                            StructuredCloneHolder* aHolder);

  void StartDelayedAutoplayMediaComponents();

  void ResetGVAutoplayRequestStatus();

  /**
   * Information required to initialize a BrowsingContext in another process.
   * This object may be serialized over IPC.
   */
  struct IPCInitializer {
    uint64_t mId = 0;

    // IDs are used for Parent and Opener to allow for this object to be
    // deserialized before other BrowsingContext in the BrowsingContextGroup
    // have been initialized.
    uint64_t mParentId = 0;
    already_AddRefed<WindowContext> GetParent();
    already_AddRefed<BrowsingContext> GetOpener();

    uint64_t GetOpenerId() const { return mozilla::Get<IDX_OpenerId>(mFields); }

    bool mWindowless = false;
    bool mUseRemoteTabs = false;
    bool mUseRemoteSubframes = false;
    bool mHasSessionHistory = false;
    OriginAttributes mOriginAttributes;
    uint64_t mRequestContextId = 0;

    FieldTuple mFields;

    bool operator==(const IPCInitializer& aOther) const {
      return mId == aOther.mId && mParentId == aOther.mParentId &&
             mWindowless == aOther.mWindowless &&
             mUseRemoteTabs == aOther.mUseRemoteTabs &&
             mUseRemoteSubframes == aOther.mUseRemoteSubframes &&
             mOriginAttributes == aOther.mOriginAttributes &&
             mRequestContextId == aOther.mRequestContextId &&
             mFields == aOther.mFields;
    }
  };

  // Create an IPCInitializer object for this BrowsingContext.
  IPCInitializer GetIPCInitializer();

  // Create a BrowsingContext object from over IPC.
  static void CreateFromIPC(IPCInitializer&& aInitializer,
                            BrowsingContextGroup* aGroup,
                            ContentParent* aOriginProcess);

  // Performs access control to check that 'this' can access 'aTarget'.
  bool CanAccess(BrowsingContext* aTarget, bool aConsiderOpener = true);

  bool IsSandboxedFrom(BrowsingContext* aTarget);

  // The runnable will be called once there is idle time, or the top level
  // page has been loaded or if a timeout has fired.
  // Must be called only on the top level BrowsingContext.
  void AddDeprioritizedLoadRunner(nsIRunnable* aRunner);

  RefPtr<SessionStorageManager> GetSessionStorageManager();

  bool PendingInitialization() const { return mPendingInitialization; };
  void SetPendingInitialization(bool aVal) { mPendingInitialization = aVal; };

  const OriginAttributes& OriginAttributesRef() { return mOriginAttributes; }
  nsresult SetOriginAttributes(const OriginAttributes& aAttrs);

  // This should only be called on the top browsing context.
  void InitSessionHistory();

  // This will only ever return a non-null value if called on the top browsing
  // context.
  ChildSHistory* GetChildSessionHistory();

  bool CrossOriginIsolated();

 protected:
  virtual ~BrowsingContext();
  BrowsingContext(WindowContext* aParentWindow, BrowsingContextGroup* aGroup,
                  uint64_t aBrowsingContextId, Type aType,
                  FieldTuple&& aFields);

 private:
  void Attach(bool aFromIPC, ContentParent* aOriginProcess);

  // Find the special browsing context if aName is '_self', '_parent',
  // '_top', but not '_blank'. The latter is handled in FindWithName
  BrowsingContext* FindWithSpecialName(const nsAString& aName,
                                       BrowsingContext& aRequestingContext);

  // Is it early enough in the BrowsingContext's lifecycle that it is still
  // OK to set OriginAttributes?
  bool CanSetOriginAttributes();

  void AssertOriginAttributesMatchPrivateBrowsing();

  // Assert that the BrowsingContext's LoadContext flags appear coherent
  // relative to related BrowsingContexts.
  void AssertCoherentLoadContext();

  friend class ::nsOuterWindowProxy;
  friend class ::nsGlobalWindowOuter;
  friend class WindowContext;

  // Update the window proxy object that corresponds to this browsing context.
  // This should be called from the window proxy object's objectMoved hook, if
  // the object mWindowProxy points to was moved by the JS GC.
  void UpdateWindowProxy(JSObject* obj, JSObject* old) {
    if (mWindowProxy) {
      MOZ_ASSERT(mWindowProxy == old);
      mWindowProxy = obj;
    }
  }
  // Clear the window proxy object that corresponds to this browsing context.
  // This should be called if the window proxy object is finalized, or it can't
  // reach its browsing context anymore.
  void ClearWindowProxy() { mWindowProxy = nullptr; }

  friend class Location;
  friend class RemoteLocationProxy;
  /**
   * LocationProxy is the class for the native object stored as a private in a
   * RemoteLocationProxy proxy representing a Location object in a different
   * process. It forwards all operations to its BrowsingContext and aggregates
   * its refcount to that BrowsingContext.
   */
  class LocationProxy final : public LocationBase {
   public:
    MozExternalRefCountType AddRef() { return GetBrowsingContext()->AddRef(); }
    MozExternalRefCountType Release() {
      return GetBrowsingContext()->Release();
    }

   protected:
    friend class RemoteLocationProxy;
    BrowsingContext* GetBrowsingContext() override {
      return reinterpret_cast<BrowsingContext*>(
          uintptr_t(this) - offsetof(BrowsingContext, mLocation));
    }

    already_AddRefed<nsIDocShell> GetDocShell() override { return nullptr; }
  };

  // Send a given `BaseTransaction` object to the correct remote.
  void SendCommitTransaction(ContentParent* aParent,
                             const BaseTransaction& aTxn, uint64_t aEpoch);
  void SendCommitTransaction(ContentChild* aChild, const BaseTransaction& aTxn,
                             uint64_t aEpoch);

  // Ensure that opener is in the same BrowsingContextGroup.
  bool CanSet(FieldIndex<IDX_OpenerId>, const uint64_t& aValue,
              ContentParent* aSource) {
    if (aValue != 0) {
      RefPtr<BrowsingContext> opener = Get(aValue);
      return opener && opener->Group() == Group();
    }
    return true;
  }

  void DidSet(FieldIndex<IDX_UserActivationState>);

  // Ensure that we only set the flag on the top level browsingContext.
  // And then, we do a pre-order walk in the tree to refresh the
  // volume of all media elements.
  void DidSet(FieldIndex<IDX_Muted>);

  bool CanSet(FieldIndex<IDX_EmbedderInnerWindowId>, const uint64_t& aValue,
              ContentParent* aSource);

  bool CanSet(FieldIndex<IDX_CurrentInnerWindowId>, const uint64_t& aValue,
              ContentParent* aSource);

  void DidSet(FieldIndex<IDX_CurrentInnerWindowId>);

  bool CanSet(FieldIndex<IDX_IsPopupSpam>, const bool& aValue,
              ContentParent* aSource);

  void DidSet(FieldIndex<IDX_IsPopupSpam>);

  void DidSet(FieldIndex<IDX_GVAudibleAutoplayRequestStatus>);
  void DidSet(FieldIndex<IDX_GVInaudibleAutoplayRequestStatus>);

  void DidSet(FieldIndex<IDX_Loading>);

  void DidSet(FieldIndex<IDX_AncestorLoading>);

  void DidSet(FieldIndex<IDX_UserAgentOverride>);
  bool CanSet(FieldIndex<IDX_UserAgentOverride>, const nsString& aUserAgent,
              ContentParent* aSource);
  bool CanSet(FieldIndex<IDX_OrientationLock>,
              const mozilla::hal::ScreenOrientation& aOrientationLock,
              ContentParent* aSource);

  bool CanSet(FieldIndex<IDX_EmbedderElementType>,
              const Maybe<nsString>& aInitiatorType, ContentParent* aSource);

  bool CanSet(FieldIndex<IDX_MessageManagerGroup>,
              const nsString& aMessageManagerGroup, ContentParent* aSource);

  bool CanSet(FieldIndex<IDX_AllowContentRetargeting>,
              const bool& aAllowContentRetargeting, ContentParent* aSource);
  bool CanSet(FieldIndex<IDX_AllowContentRetargetingOnChildren>,
              const bool& aAllowContentRetargetingOnChildren,
              ContentParent* aSource);
  bool CanSet(FieldIndex<IDX_AllowPlugins>, const bool& aAllowPlugins,
              ContentParent* aSource);
  bool CanSet(FieldIndex<IDX_FullscreenAllowedByOwner>, const bool&,
              ContentParent*);
  bool CanSet(FieldIndex<IDX_WatchedByDevToolsInternal>,
              const bool& aWatchedByDevToolsInternal, ContentParent* aSource);

  bool CanSet(FieldIndex<IDX_DefaultLoadFlags>,
              const uint32_t& aDefaultLoadFlags, ContentParent* aSource);
  void DidSet(FieldIndex<IDX_DefaultLoadFlags>);

  bool CanSet(FieldIndex<IDX_UseGlobalHistory>, const bool& aUseGlobalHistory,
              ContentParent* aSource);

  void DidSet(FieldIndex<IDX_HasSessionHistory>, bool aOldValue);

  template <size_t I, typename T>
  bool CanSet(FieldIndex<I>, const T&, ContentParent*) {
    return true;
  }

  // Overload `DidSet` to get notifications for a particular field being set.
  //
  // You can also overload the variant that gets the old value if you need it.
  template <size_t I>
  void DidSet(FieldIndex<I>) {}
  template <size_t I, typename T>
  void DidSet(FieldIndex<I>, T&& aOldValue) {}

  void DidSet(FieldIndex<IDX_FullZoom>, float aOldValue);
  void DidSet(FieldIndex<IDX_TextZoom>, float aOldValue);

  // True if the process attemping to set field is the same as the owning
  // process.
  bool CheckOnlyOwningProcessCanSet(ContentParent* aSource);

  // True if the process attempting to set field is the same as the embedder's
  // process.
  bool CheckOnlyEmbedderCanSet(ContentParent* aSource);

  void CreateChildSHistory();

  // Type of BrowsingContent
  const Type mType;

  // Unique id identifying BrowsingContext
  const uint64_t mBrowsingContextId;

  RefPtr<BrowsingContextGroup> mGroup;
  RefPtr<WindowContext> mParentWindow;
  nsCOMPtr<nsIDocShell> mDocShell;

  RefPtr<Element> mEmbedderElement;

  nsTArray<RefPtr<WindowContext>> mWindowContexts;
  RefPtr<WindowContext> mCurrentWindowContext;

  // This is not a strong reference, but using a JS::Heap for that should be
  // fine. The JSObject stored in here should be a proxy with a
  // nsOuterWindowProxy handler, which will update the pointer from its
  // objectMoved hook and clear it from its finalize hook.
  JS::Heap<JSObject*> mWindowProxy;
  LocationProxy mLocation;

  // OriginAttributes for this BrowsingContext. May not be changed after this
  // BrowsingContext is attached.
  OriginAttributes mOriginAttributes;

  // The network request context id, representing the nsIRequestContext
  // associated with this BrowsingContext, and LoadGroups created for it.
  uint64_t mRequestContextId = 0;

  // Determines if private browsing should be used. May not be changed after
  // this BrowsingContext is attached. This field matches mOriginAttributes in
  // content Browsing Contexts. Currently treated as a binary value: 1 - in
  // private mode, 0 - not private mode.
  uint32_t mPrivateBrowsingId;

  // True if Attach() has been called on this BrowsingContext already.
  bool mEverAttached : 1;

  // Is the most recent Document in this BrowsingContext loaded within this
  // process? This may be true with a null mDocShell after the Window has been
  // closed.
  bool mIsInProcess : 1;

  // Has this browsing context been discarded? BrowsingContexts should
  // only be discarded once.
  bool mIsDiscarded : 1;

  // True if this BrowsingContext has no associated visible window, and is owned
  // by whichever process created it, even if top-level.
  bool mWindowless : 1;

  // This is true if the BrowsingContext was out of process, but is now in
  // process, and might have remote window proxies that need to be cleaned up.
  bool mDanglingRemoteOuterProxies : 1;

  // If true, the docShell has not been fully initialized, and may not be used
  // as the target of a load.
  bool mPendingInitialization : 1;

  // True if this BrowsingContext has been embedded in a element in this
  // process.
  bool mEmbeddedByThisProcess : 1;

  // Determines if remote (out-of-process) tabs should be used. May not be
  // changed after this BrowsingContext is attached.
  bool mUseRemoteTabs : 1;

  // Determines if out-of-process iframes should be used. May not be changed
  // after this BrowsingContext is attached.
  bool mUseRemoteSubframes : 1;

  // The start time of user gesture, this is only available if the browsing
  // context is in process.
  TimeStamp mUserGestureStart;

  class DeprioritizedLoadRunner
      : public mozilla::Runnable,
        public mozilla::LinkedListElement<DeprioritizedLoadRunner> {
   public:
    explicit DeprioritizedLoadRunner(nsIRunnable* aInner)
        : Runnable("DeprioritizedLoadRunner"), mInner(aInner) {}

    NS_IMETHOD Run() override {
      if (mInner) {
        RefPtr<nsIRunnable> inner = std::move(mInner);
        inner->Run();
      }

      return NS_OK;
    }

   private:
    RefPtr<nsIRunnable> mInner;
  };

  mozilla::LinkedList<DeprioritizedLoadRunner> mDeprioritizedLoadRunner;

  RefPtr<SessionStorageManager> mSessionStorageManager;
  RefPtr<ChildSHistory> mChildSessionHistory;
};

/**
 * Gets a WindowProxy object for a BrowsingContext that lives in a different
 * process (creating the object if it doesn't already exist). The WindowProxy
 * object will be in the compartment that aCx is currently in. This should only
 * be called if aContext doesn't hold a docshell, otherwise the BrowsingContext
 * lives in this process, and a same-process WindowProxy should be used (see
 * nsGlobalWindowOuter). This should only be called by bindings code, ToJSValue
 * is the right API to get a WindowProxy for a BrowsingContext.
 *
 * If aTransplantTo is non-null, then the WindowProxy object will eventually be
 * transplanted onto it. Therefore it should be used as the value in the remote
 * proxy map.
 */
extern bool GetRemoteOuterWindowProxy(JSContext* aCx, BrowsingContext* aContext,
                                      JS::Handle<JSObject*> aTransplantTo,
                                      JS::MutableHandle<JSObject*> aRetVal);

using BrowsingContextTransaction = BrowsingContext::BaseTransaction;
using BrowsingContextInitializer = BrowsingContext::IPCInitializer;
using MaybeDiscardedBrowsingContext = MaybeDiscarded<BrowsingContext>;

// Specialize the transaction object for every translation unit it's used in.
extern template class syncedcontext::Transaction<BrowsingContext>;

}  // namespace dom

// Allow sending BrowsingContext objects over IPC.
namespace ipc {
template <>
struct IPDLParamTraits<dom::MaybeDiscarded<dom::BrowsingContext>> {
  static void Write(IPC::Message* aMsg, IProtocol* aActor,
                    const dom::MaybeDiscarded<dom::BrowsingContext>& aParam);
  static bool Read(const IPC::Message* aMsg, PickleIterator* aIter,
                   IProtocol* aActor,
                   dom::MaybeDiscarded<dom::BrowsingContext>* aResult);
};

template <>
struct IPDLParamTraits<dom::BrowsingContext::IPCInitializer> {
  static void Write(IPC::Message* aMessage, IProtocol* aActor,
                    const dom::BrowsingContext::IPCInitializer& aInitializer);

  static bool Read(const IPC::Message* aMessage, PickleIterator* aIterator,
                   IProtocol* aActor,
                   dom::BrowsingContext::IPCInitializer* aInitializer);
};
}  // namespace ipc
}  // namespace mozilla

#endif  // !defined(mozilla_dom_BrowsingContext_h)