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Diffstat (limited to 'accessible/generic/DocAccessible.cpp')
| -rw-r--r-- | accessible/generic/DocAccessible.cpp | 2771 |
1 files changed, 2771 insertions, 0 deletions
diff --git a/accessible/generic/DocAccessible.cpp b/accessible/generic/DocAccessible.cpp new file mode 100644 index 0000000000..fda332ebe0 --- /dev/null +++ b/accessible/generic/DocAccessible.cpp @@ -0,0 +1,2771 @@ +/* -*- 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/. */ + +#include "LocalAccessible-inl.h" +#include "AccIterator.h" +#include "AccAttributes.h" +#include "CachedTableAccessible.h" +#include "DocAccessible-inl.h" +#include "DocAccessibleChild.h" +#include "EventTree.h" +#include "HTMLImageMapAccessible.h" +#include "mozilla/ProfilerMarkers.h" +#include "nsAccCache.h" +#include "nsAccessiblePivot.h" +#include "nsAccUtils.h" +#include "nsEventShell.h" +#include "nsIIOService.h" +#include "nsLayoutUtils.h" +#include "nsTextEquivUtils.h" +#include "Pivot.h" +#include "Role.h" +#include "RootAccessible.h" +#include "TreeWalker.h" +#include "xpcAccessibleDocument.h" + +#include "nsCommandManager.h" +#include "nsContentUtils.h" +#include "nsIDocShell.h" +#include "mozilla/dom/Document.h" +#include "nsPIDOMWindow.h" +#include "nsIContentInlines.h" +#include "nsIEditingSession.h" +#include "nsIFrame.h" +#include "nsIInterfaceRequestorUtils.h" +#include "nsImageFrame.h" +#include "nsViewManager.h" +#include "nsIScrollableFrame.h" +#include "nsUnicharUtils.h" +#include "nsIURI.h" +#include "nsIWebNavigation.h" +#include "nsFocusManager.h" +#include "nsTHashSet.h" +#include "mozilla/ArrayUtils.h" +#include "mozilla/Assertions.h" +#include "mozilla/Components.h" // for mozilla::components +#include "mozilla/EditorBase.h" +#include "mozilla/HTMLEditor.h" +#include "mozilla/ipc/ProcessChild.h" +#include "mozilla/PresShell.h" +#include "nsAccessibilityService.h" +#include "mozilla/a11y/DocAccessibleParent.h" +#include "mozilla/dom/AncestorIterator.h" +#include "mozilla/dom/BrowserChild.h" +#include "mozilla/dom/BrowserParent.h" +#include "mozilla/dom/DocumentType.h" +#include "mozilla/dom/Element.h" +#include "mozilla/dom/HTMLSelectElement.h" +#include "mozilla/dom/MutationEventBinding.h" +#include "mozilla/dom/UserActivation.h" + +using namespace mozilla; +using namespace mozilla::a11y; + +//////////////////////////////////////////////////////////////////////////////// +// Static member initialization + +static nsStaticAtom* const kRelationAttrs[] = {nsGkAtoms::aria_labelledby, + nsGkAtoms::aria_describedby, + nsGkAtoms::aria_details, + nsGkAtoms::aria_owns, + nsGkAtoms::aria_controls, + nsGkAtoms::aria_flowto, + nsGkAtoms::aria_errormessage, + nsGkAtoms::_for, + nsGkAtoms::control}; + +static const uint32_t kRelationAttrsLen = ArrayLength(kRelationAttrs); + +//////////////////////////////////////////////////////////////////////////////// +// Constructor/desctructor + +DocAccessible::DocAccessible(dom::Document* aDocument, + PresShell* aPresShell) + : // XXX don't pass a document to the LocalAccessible constructor so that + // we don't set mDoc until our vtable is fully setup. If we set mDoc + // before setting up the vtable we will call LocalAccessible::AddRef() + // but not the overrides of it for subclasses. It is important to call + // those overrides to avoid confusing leak checking machinary. + HyperTextAccessibleWrap(nullptr, nullptr), + // XXX aaronl should we use an algorithm for the initial cache size? + mAccessibleCache(kDefaultCacheLength), + mNodeToAccessibleMap(kDefaultCacheLength), + mDocumentNode(aDocument), + mLoadState(eTreeConstructionPending), + mDocFlags(0), + mViewportCacheDirty(false), + mLoadEventType(0), + mPrevStateBits(0), + mVirtualCursor(nullptr), + mPresShell(aPresShell), + mIPCDoc(nullptr) { + mGenericTypes |= eDocument; + mStateFlags |= eNotNodeMapEntry; + mDoc = this; + + MOZ_ASSERT(mPresShell, "should have been given a pres shell"); + mPresShell->SetDocAccessible(this); +} + +DocAccessible::~DocAccessible() { + NS_ASSERTION(!mPresShell, "LastRelease was never called!?!"); +} + +//////////////////////////////////////////////////////////////////////////////// +// nsISupports + +NS_IMPL_CYCLE_COLLECTION_CLASS(DocAccessible) + +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(DocAccessible, + LocalAccessible) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mNotificationController) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mVirtualCursor) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mChildDocuments) + for (const auto& hashEntry : tmp->mDependentIDsHashes.Values()) { + for (const auto& providers : hashEntry->Values()) { + for (int32_t provIdx = providers->Length() - 1; provIdx >= 0; provIdx--) { + NS_CYCLE_COLLECTION_NOTE_EDGE_NAME( + cb, "content of dependent ids hash entry of document accessible"); + + const auto& provider = (*providers)[provIdx]; + cb.NoteXPCOMChild(provider->mContent); + } + } + } + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mAccessibleCache) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mAnchorJumpElm) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mInvalidationList) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingUpdates) + for (const auto& ar : tmp->mARIAOwnsHash.Values()) { + for (uint32_t i = 0; i < ar->Length(); i++) { + NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mARIAOwnsHash entry item"); + cb.NoteXPCOMChild(ar->ElementAt(i)); + } + } +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(DocAccessible, LocalAccessible) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mNotificationController) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mVirtualCursor) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mChildDocuments) + tmp->mDependentIDsHashes.Clear(); + tmp->mNodeToAccessibleMap.Clear(); + NS_IMPL_CYCLE_COLLECTION_UNLINK(mAccessibleCache) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mAnchorJumpElm) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mInvalidationList) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mPendingUpdates) + NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE + tmp->mARIAOwnsHash.Clear(); +NS_IMPL_CYCLE_COLLECTION_UNLINK_END + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DocAccessible) + NS_INTERFACE_MAP_ENTRY(nsIDocumentObserver) + NS_INTERFACE_MAP_ENTRY(nsIMutationObserver) + NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference) + NS_INTERFACE_MAP_ENTRY(nsIAccessiblePivotObserver) +NS_INTERFACE_MAP_END_INHERITING(HyperTextAccessible) + +NS_IMPL_ADDREF_INHERITED(DocAccessible, HyperTextAccessible) +NS_IMPL_RELEASE_INHERITED(DocAccessible, HyperTextAccessible) + +//////////////////////////////////////////////////////////////////////////////// +// nsIAccessible + +ENameValueFlag DocAccessible::Name(nsString& aName) const { + aName.Truncate(); + + if (mParent) { + mParent->Name(aName); // Allow owning iframe to override the name + } + if (aName.IsEmpty()) { + // Allow name via aria-labelledby or title attribute + LocalAccessible::Name(aName); + } + if (aName.IsEmpty()) { + Title(aName); // Try title element + } + if (aName.IsEmpty()) { // Last resort: use URL + URL(aName); + } + + return eNameOK; +} + +// LocalAccessible public method +role DocAccessible::NativeRole() const { + nsCOMPtr<nsIDocShell> docShell = nsCoreUtils::GetDocShellFor(mDocumentNode); + if (docShell) { + nsCOMPtr<nsIDocShellTreeItem> sameTypeRoot; + docShell->GetInProcessSameTypeRootTreeItem(getter_AddRefs(sameTypeRoot)); + int32_t itemType = docShell->ItemType(); + if (sameTypeRoot == docShell) { + // Root of content or chrome tree + if (itemType == nsIDocShellTreeItem::typeChrome) { + return roles::CHROME_WINDOW; + } + + if (itemType == nsIDocShellTreeItem::typeContent) { + return roles::DOCUMENT; + } + } else if (itemType == nsIDocShellTreeItem::typeContent) { + return roles::DOCUMENT; + } + } + + return roles::PANE; // Fall back; +} + +void DocAccessible::Description(nsString& aDescription) const { + if (mParent) mParent->Description(aDescription); + + if (HasOwnContent() && aDescription.IsEmpty()) { + nsTextEquivUtils::GetTextEquivFromIDRefs(this, nsGkAtoms::aria_describedby, + aDescription); + } +} + +// LocalAccessible public method +uint64_t DocAccessible::NativeState() const { + // Document is always focusable. + uint64_t state = + states::FOCUSABLE; // keep in sync with NativeInteractiveState() impl + if (FocusMgr()->IsFocused(this)) state |= states::FOCUSED; + + // Expose stale state until the document is ready (DOM is loaded and tree is + // constructed). + if (!HasLoadState(eReady)) state |= states::STALE; + + // Expose state busy until the document and all its subdocuments is completely + // loaded. + if (!HasLoadState(eCompletelyLoaded)) state |= states::BUSY; + + nsIFrame* frame = GetFrame(); + if (!frame || !frame->IsVisibleConsideringAncestors( + nsIFrame::VISIBILITY_CROSS_CHROME_CONTENT_BOUNDARY)) { + state |= states::INVISIBLE | states::OFFSCREEN; + } + + RefPtr<EditorBase> editorBase = GetEditor(); + state |= editorBase ? states::EDITABLE : states::READONLY; + + return state; +} + +uint64_t DocAccessible::NativeInteractiveState() const { + // Document is always focusable. + return states::FOCUSABLE; +} + +bool DocAccessible::NativelyUnavailable() const { return false; } + +// LocalAccessible public method +void DocAccessible::ApplyARIAState(uint64_t* aState) const { + // Grab states from content element. + if (mContent) LocalAccessible::ApplyARIAState(aState); + + // Allow iframe/frame etc. to have final state override via ARIA. + if (mParent) mParent->ApplyARIAState(aState); +} + +Accessible* DocAccessible::FocusedChild() { + // Return an accessible for the current global focus, which does not have to + // be contained within the current document. + return FocusMgr()->FocusedAccessible(); +} + +void DocAccessible::TakeFocus() const { + // Focus the document. + nsFocusManager* fm = nsFocusManager::GetFocusManager(); + RefPtr<dom::Element> newFocus; + dom::AutoHandlingUserInputStatePusher inputStatePusher(true); + fm->MoveFocus(mDocumentNode->GetWindow(), nullptr, + nsFocusManager::MOVEFOCUS_ROOT, 0, getter_AddRefs(newFocus)); +} + +// HyperTextAccessible method +already_AddRefed<EditorBase> DocAccessible::GetEditor() const { + // Check if document is editable (designMode="on" case). Otherwise check if + // the html:body (for HTML document case) or document element is editable. + if (!mDocumentNode->IsInDesignMode() && + (!mContent || !mContent->HasFlag(NODE_IS_EDITABLE))) { + return nullptr; + } + + nsCOMPtr<nsIDocShell> docShell = mDocumentNode->GetDocShell(); + if (!docShell) { + return nullptr; + } + + nsCOMPtr<nsIEditingSession> editingSession; + docShell->GetEditingSession(getter_AddRefs(editingSession)); + if (!editingSession) return nullptr; // No editing session interface + + RefPtr<HTMLEditor> htmlEditor = + editingSession->GetHTMLEditorForWindow(mDocumentNode->GetWindow()); + if (!htmlEditor) { + return nullptr; + } + + bool isEditable = false; + htmlEditor->GetIsDocumentEditable(&isEditable); + if (isEditable) { + return htmlEditor.forget(); + } + + return nullptr; +} + +// DocAccessible public method + +void DocAccessible::URL(nsAString& aURL) const { + aURL.Truncate(); + nsCOMPtr<nsISupports> container = mDocumentNode->GetContainer(); + nsCOMPtr<nsIWebNavigation> webNav(do_GetInterface(container)); + if (MOZ_UNLIKELY(!webNav)) { + return; + } + + nsCOMPtr<nsIURI> uri; + webNav->GetCurrentURI(getter_AddRefs(uri)); + if (MOZ_UNLIKELY(!uri)) { + return; + } + // Let's avoid treating too long URI in the main process for avoiding + // memory fragmentation as far as possible. + if (uri->SchemeIs("data") || uri->SchemeIs("blob")) { + return; + } + + nsCOMPtr<nsIIOService> io = mozilla::components::IO::Service(); + if (NS_WARN_IF(!io)) { + return; + } + nsCOMPtr<nsIURI> exposableURI; + if (NS_FAILED(io->CreateExposableURI(uri, getter_AddRefs(exposableURI))) || + MOZ_UNLIKELY(!exposableURI)) { + return; + } + nsAutoCString theURL; + if (NS_SUCCEEDED(exposableURI->GetSpec(theURL))) { + CopyUTF8toUTF16(theURL, aURL); + } +} + +void DocAccessible::Title(nsString& aTitle) const { + mDocumentNode->GetTitle(aTitle); +} + +void DocAccessible::MimeType(nsAString& aType) const { + mDocumentNode->GetContentType(aType); +} + +void DocAccessible::DocType(nsAString& aType) const { + dom::DocumentType* docType = mDocumentNode->GetDoctype(); + if (docType) docType->GetPublicId(aType); +} + +void DocAccessible::QueueCacheUpdate(LocalAccessible* aAcc, + uint64_t aNewDomain) { + if (!mIPCDoc) { + return; + } + uint64_t& domain = mQueuedCacheUpdates.LookupOrInsert(aAcc, 0); + domain |= aNewDomain; + Controller()->ScheduleProcessing(); +} + +void DocAccessible::QueueCacheUpdateForDependentRelations( + LocalAccessible* aAcc) { + if (!mIPCDoc || !aAcc || !aAcc->Elm() || !aAcc->IsInDocument() || + aAcc->IsDefunct()) { + return; + } + nsAutoString ID; + aAcc->DOMNodeID(ID); + if (AttrRelProviders* list = GetRelProviders(aAcc->Elm(), ID)) { + // We call this function when we've noticed an ID change, or when an acc + // is getting bound to its document. We need to ensure any existing accs + // that depend on this acc's ID have their rel cache entries updated. + for (const auto& provider : *list) { + LocalAccessible* relatedAcc = GetAccessible(provider->mContent); + if (!relatedAcc || relatedAcc->IsDefunct() || + !relatedAcc->IsInDocument() || + mInsertedAccessibles.Contains(relatedAcc)) { + continue; + } + QueueCacheUpdate(relatedAcc, CacheDomain::Relations); + } + } +} + +//////////////////////////////////////////////////////////////////////////////// +// LocalAccessible + +void DocAccessible::Init() { +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eDocCreate)) { + logging::DocCreate("document initialize", mDocumentNode, this); + } +#endif + + // Initialize notification controller. + mNotificationController = new NotificationController(this, mPresShell); + + // Mark the DocAccessible as loaded if its DOM document is already loaded at + // this point. This can happen for one of three reasons: + // 1. A11y was started late. + // 2. DOM loading for a document (probably an in-process iframe) completed + // before its Accessible container was created. + // 3. The PresShell for the document was created after DOM loading completed. + // In that case, we tried to create the DocAccessible when DOM loading + // completed, but we can't create a DocAccessible without a PresShell, so + // this failed. The DocAccessible was subsequently created due to a layout + // notification. + if (mDocumentNode->GetReadyStateEnum() == + dom::Document::READYSTATE_COMPLETE) { + mLoadState |= eDOMLoaded; + // If this happened due to reasons 1 or 2, it isn't *necessary* to fire a + // doc load complete event. If it happened due to reason 3, we need to fire + // doc load complete because clients (especially tests) might be waiting + // for the document to load using this event. We can't distinguish why this + // happened at this point, so just fire it regardless. It won't do any + // harm even if it isn't necessary. We set mLoadEventType here and it will + // be fired in ProcessLoad as usual. + mLoadEventType = nsIAccessibleEvent::EVENT_DOCUMENT_LOAD_COMPLETE; + } else if (mDocumentNode->IsInitialDocument()) { + // The initial about:blank document will never finish loading, so we can + // immediately mark it loaded to avoid waiting for its load. + mLoadState |= eDOMLoaded; + } + + AddEventListeners(); +} + +void DocAccessible::Shutdown() { + if (!mPresShell) { // already shutdown + return; + } + +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eDocDestroy)) { + logging::DocDestroy("document shutdown", mDocumentNode, this); + } +#endif + + // Mark the document as shutdown before AT is notified about the document + // removal from its container (valid for root documents on ATK and due to + // some reason for MSAA, refer to bug 757392 for details). + mStateFlags |= eIsDefunct; + + if (mNotificationController) { + mNotificationController->Shutdown(); + mNotificationController = nullptr; + } + + RemoveEventListeners(); + + // mParent->RemoveChild clears mParent, but we need to know whether we were a + // child later, so use a flag. + const bool isChild = !!mParent; + if (mParent) { + DocAccessible* parentDocument = mParent->Document(); + if (parentDocument) parentDocument->RemoveChildDocument(this); + + mParent->RemoveChild(this); + MOZ_ASSERT(!mParent, "Parent has to be null!"); + } + + mPresShell->SetDocAccessible(nullptr); + mPresShell = nullptr; // Avoid reentrancy + + // Walk the array backwards because child documents remove themselves from the + // array as they are shutdown. + int32_t childDocCount = mChildDocuments.Length(); + for (int32_t idx = childDocCount - 1; idx >= 0; idx--) { + mChildDocuments[idx]->Shutdown(); + } + + mChildDocuments.Clear(); + // mQueuedCacheUpdates can contain a reference to this document (ex. if the + // doc is scrollable and we're sending a scroll position update). Clear the + // map here to avoid creating ref cycles. + mQueuedCacheUpdates.Clear(); + + // XXX thinking about ordering? + if (mIPCDoc) { + MOZ_ASSERT(IPCAccessibilityActive()); + mIPCDoc->Shutdown(); + MOZ_ASSERT(!mIPCDoc); + } + + if (mVirtualCursor) { + mVirtualCursor->RemoveObserver(this); + mVirtualCursor = nullptr; + } + + mDependentIDsHashes.Clear(); + mNodeToAccessibleMap.Clear(); + + mAnchorJumpElm = nullptr; + mInvalidationList.Clear(); + mPendingUpdates.Clear(); + + for (auto iter = mAccessibleCache.Iter(); !iter.Done(); iter.Next()) { + LocalAccessible* accessible = iter.Data(); + MOZ_ASSERT(accessible); + if (accessible) { + // This might have been focused with FocusManager::ActiveItemChanged. In + // that case, we must notify FocusManager so that it clears the active + // item. Otherwise, it will hold on to a defunct Accessible. Normally, + // this happens in UnbindFromDocument, but we don't call that when the + // whole document shuts down. + if (FocusMgr()->WasLastFocused(accessible)) { + FocusMgr()->ActiveItemChanged(nullptr); +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eFocus)) { + logging::ActiveItemChangeCausedBy("doc shutdown", accessible); + } +#endif + } + if (!accessible->IsDefunct()) { + // Unlink parent to avoid its cleaning overhead in shutdown. + accessible->mParent = nullptr; + accessible->Shutdown(); + } + } + iter.Remove(); + } + + HyperTextAccessibleWrap::Shutdown(); + + MOZ_ASSERT(GetAccService()); + GetAccService()->NotifyOfDocumentShutdown( + this, mDocumentNode, + // Make sure we don't shut down AccService while a parent document is + // still shutting down. The parent will allow service shutdown when it + // reaches this point. + /* aAllowServiceShutdown */ !isChild); + mDocumentNode = nullptr; +} + +nsIFrame* DocAccessible::GetFrame() const { + nsIFrame* root = nullptr; + if (mPresShell) { + root = mPresShell->GetRootFrame(); + } + + return root; +} + +nsINode* DocAccessible::GetNode() const { return mDocumentNode; } + +// DocAccessible protected member +nsRect DocAccessible::RelativeBounds(nsIFrame** aRelativeFrame) const { + *aRelativeFrame = GetFrame(); + + dom::Document* document = mDocumentNode; + dom::Document* parentDoc = nullptr; + + nsRect bounds; + while (document) { + PresShell* presShell = document->GetPresShell(); + if (!presShell) { + return nsRect(); + } + + nsRect scrollPort; + nsIScrollableFrame* sf = presShell->GetRootScrollFrameAsScrollable(); + if (sf) { + scrollPort = sf->GetScrollPortRect(); + } else { + nsIFrame* rootFrame = presShell->GetRootFrame(); + if (!rootFrame) return nsRect(); + + scrollPort = rootFrame->GetRect(); + } + + if (parentDoc) { // After first time thru loop + // XXXroc bogus code! scrollPort is relative to the viewport of + // this document, but we're intersecting rectangles derived from + // multiple documents and assuming they're all in the same coordinate + // system. See bug 514117. + bounds.IntersectRect(scrollPort, bounds); + } else { // First time through loop + bounds = scrollPort; + } + + document = parentDoc = document->GetInProcessParentDocument(); + } + + return bounds; +} + +// DocAccessible protected member +nsresult DocAccessible::AddEventListeners() { + SelectionMgr()->AddDocSelectionListener(mPresShell); + + // Add document observer. + mDocumentNode->AddObserver(this); + return NS_OK; +} + +// DocAccessible protected member +nsresult DocAccessible::RemoveEventListeners() { + // Remove listeners associated with content documents + NS_ASSERTION(mDocumentNode, "No document during removal of listeners."); + + if (mDocumentNode) { + mDocumentNode->RemoveObserver(this); + } + + if (mScrollWatchTimer) { + mScrollWatchTimer->Cancel(); + mScrollWatchTimer = nullptr; + NS_RELEASE_THIS(); // Kung fu death grip + } + + SelectionMgr()->RemoveDocSelectionListener(mPresShell); + return NS_OK; +} + +void DocAccessible::ScrollTimerCallback(nsITimer* aTimer, void* aClosure) { + DocAccessible* docAcc = reinterpret_cast<DocAccessible*>(aClosure); + + if (docAcc) { + // Dispatch a scroll-end for all entries in table. They have not + // been scrolled in at least `kScrollEventInterval`. + for (auto iter = docAcc->mLastScrollingDispatch.Iter(); !iter.Done(); + iter.Next()) { + docAcc->DispatchScrollingEvent(iter.Key(), + nsIAccessibleEvent::EVENT_SCROLLING_END); + iter.Remove(); + } + + if (docAcc->mScrollWatchTimer) { + docAcc->mScrollWatchTimer = nullptr; + NS_RELEASE(docAcc); // Release kung fu death grip + } + } +} + +void DocAccessible::HandleScroll(nsINode* aTarget) { + nsINode* target = aTarget; + LocalAccessible* targetAcc = GetAccessible(target); + if (!targetAcc && target->IsInNativeAnonymousSubtree()) { + // The scroll event for textareas comes from a native anonymous div. We need + // the closest non-anonymous ancestor to get the right Accessible. + target = target->GetClosestNativeAnonymousSubtreeRootParentOrHost(); + targetAcc = GetAccessible(target); + } + // Regardless of our scroll timer, we need to send a cache update + // to ensure the next Bounds() query accurately reflects our position + // after scrolling. + if (targetAcc) { + QueueCacheUpdate(targetAcc, CacheDomain::ScrollPosition); + } + + const uint32_t kScrollEventInterval = 100; + // If we haven't dispatched a scrolling event for a target in at least + // kScrollEventInterval milliseconds, dispatch one now. + mLastScrollingDispatch.WithEntryHandle(target, [&](auto&& lastDispatch) { + const TimeStamp now = TimeStamp::Now(); + + if (!lastDispatch || + (now - lastDispatch.Data()).ToMilliseconds() >= kScrollEventInterval) { + // We can't fire events on a document whose tree isn't constructed yet. + if (HasLoadState(eTreeConstructed)) { + DispatchScrollingEvent(target, nsIAccessibleEvent::EVENT_SCROLLING); + } + lastDispatch.InsertOrUpdate(now); + } + }); + + // If timer callback is still pending, push it 100ms into the future. + // When scrolling ends and we don't fire this callback anymore, the + // timer callback will fire and dispatch an EVENT_SCROLLING_END. + if (mScrollWatchTimer) { + mScrollWatchTimer->SetDelay(kScrollEventInterval); + } else { + NS_NewTimerWithFuncCallback(getter_AddRefs(mScrollWatchTimer), + ScrollTimerCallback, this, kScrollEventInterval, + nsITimer::TYPE_ONE_SHOT, + "a11y::DocAccessible::ScrollPositionDidChange"); + if (mScrollWatchTimer) { + NS_ADDREF_THIS(); // Kung fu death grip + } + } +} + +std::pair<nsPoint, nsRect> DocAccessible::ComputeScrollData( + LocalAccessible* aAcc) { + nsPoint scrollPoint; + nsRect scrollRange; + + if (nsIFrame* frame = aAcc->GetFrame()) { + nsIScrollableFrame* sf = aAcc == this + ? mPresShell->GetRootScrollFrameAsScrollable() + : frame->GetScrollTargetFrame(); + + // If there is no scrollable frame, it's likely a scroll in a popup, like + // <select>. Return a scroll offset and range of 0. The scroll info + // is currently only used on Android, and popups are rendered natively + // there. + if (sf) { + scrollPoint = sf->GetScrollPosition() * mPresShell->GetResolution(); + scrollRange = sf->GetScrollRange(); + scrollRange.ScaleRoundOut(mPresShell->GetResolution()); + } + } + + return {scrollPoint, scrollRange}; +} + +//////////////////////////////////////////////////////////////////////////////// +// nsIAccessiblePivotObserver + +NS_IMETHODIMP +DocAccessible::OnPivotChanged(nsIAccessiblePivot* aPivot, + nsIAccessible* aOldAccessible, int32_t aOldStart, + int32_t aOldEnd, nsIAccessible* aNewAccessible, + int32_t aNewStart, int32_t aNewEnd, + PivotMoveReason aReason, + TextBoundaryType aBoundaryType, + bool aIsFromUserInput) { + RefPtr<AccEvent> event = new AccVCChangeEvent( + this, (aOldAccessible ? aOldAccessible->ToInternalAccessible() : nullptr), + aOldStart, aOldEnd, + (aNewAccessible ? aNewAccessible->ToInternalAccessible() : nullptr), + aNewStart, aNewEnd, aReason, aBoundaryType, + aIsFromUserInput ? eFromUserInput : eNoUserInput); + nsEventShell::FireEvent(event); + + return NS_OK; +} + +//////////////////////////////////////////////////////////////////////////////// +// nsIDocumentObserver + +NS_IMPL_NSIDOCUMENTOBSERVER_CORE_STUB(DocAccessible) +NS_IMPL_NSIDOCUMENTOBSERVER_LOAD_STUB(DocAccessible) + +void DocAccessible::AttributeWillChange(dom::Element* aElement, + int32_t aNameSpaceID, + nsAtom* aAttribute, int32_t aModType) { + LocalAccessible* accessible = GetAccessible(aElement); + if (!accessible) { + if (aElement != mContent) return; + + accessible = this; + } + + // Update dependent IDs cache. Take care of elements that are accessible + // because dependent IDs cache doesn't contain IDs from non accessible + // elements. + if (aModType != dom::MutationEvent_Binding::ADDITION) { + RemoveDependentIDsFor(accessible, aAttribute); + } + + if (aAttribute == nsGkAtoms::id) { + if (accessible->IsActiveDescendant()) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(accessible, states::ACTIVE, false); + FireDelayedEvent(event); + } + + RelocateARIAOwnedIfNeeded(aElement); + } + + if (aAttribute == nsGkAtoms::aria_activedescendant) { + if (LocalAccessible* activeDescendant = accessible->CurrentItem()) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(activeDescendant, states::ACTIVE, false); + FireDelayedEvent(event); + } + } + + // If attribute affects accessible's state, store the old state so we can + // later compare it against the state of the accessible after the attribute + // change. + if (accessible->AttributeChangesState(aAttribute)) { + mPrevStateBits = accessible->State(); + } else { + mPrevStateBits = 0; + } +} + +void DocAccessible::AttributeChanged(dom::Element* aElement, + int32_t aNameSpaceID, nsAtom* aAttribute, + int32_t aModType, + const nsAttrValue* aOldValue) { + NS_ASSERTION(!IsDefunct(), + "Attribute changed called on defunct document accessible!"); + + // Proceed even if the element is not accessible because element may become + // accessible if it gets certain attribute. + if (UpdateAccessibleOnAttrChange(aElement, aAttribute)) return; + + // Update the accessible tree on aria-hidden change. Make sure to not create + // a tree under aria-hidden='true'. + if (aAttribute == nsGkAtoms::aria_hidden) { + if (aria::HasDefinedARIAHidden(aElement)) { + ContentRemoved(aElement); + } else { + ContentInserted(aElement, aElement->GetNextSibling()); + } + return; + } + + LocalAccessible* accessible = GetAccessible(aElement); + if (!accessible) { + if (mContent == aElement) { + // The attribute change occurred on the root content of this + // DocAccessible, so handle it as an attribute change on this. + accessible = this; + } else { + if (aModType == dom::MutationEvent_Binding::ADDITION && + aria::AttrCharacteristicsFor(aAttribute) & ATTR_GLOBAL) { + // The element doesn't have an Accessible, but a global ARIA attribute + // was just added, which means we should probably create an Accessible. + ContentInserted(aElement, aElement->GetNextSibling()); + return; + } + // The element doesn't have an Accessible, so ignore the attribute + // change. + return; + } + } + + MOZ_ASSERT(accessible->IsBoundToParent() || accessible->IsDoc(), + "DOM attribute change on an accessible detached from the tree"); + + if (aAttribute == nsGkAtoms::id) { + dom::Element* elm = accessible->Elm(); + RelocateARIAOwnedIfNeeded(elm); + ARIAActiveDescendantIDMaybeMoved(accessible); + QueueCacheUpdate(accessible, CacheDomain::DOMNodeIDAndClass); + QueueCacheUpdateForDependentRelations(accessible); + } + + // The activedescendant universal property redirects accessible focus events + // to the element with the id that activedescendant points to. Make sure + // the tree up to date before processing. In other words, when a node has just + // been inserted, the tree won't be up to date yet, so we must always schedule + // an async notification so that a newly inserted node will be present in + // the tree. + if (aAttribute == nsGkAtoms::aria_activedescendant) { + mNotificationController + ->ScheduleNotification<DocAccessible, LocalAccessible>( + this, &DocAccessible::ARIAActiveDescendantChanged, accessible); + return; + } + + // Defer to accessible any needed actions like changing states or emiting + // events. + accessible->DOMAttributeChanged(aNameSpaceID, aAttribute, aModType, aOldValue, + mPrevStateBits); + + // Update dependent IDs cache. We handle elements with accessibles. + // If the accessible or element with the ID doesn't exist yet the cache will + // be updated when they are added. + if (aModType == dom::MutationEvent_Binding::MODIFICATION || + aModType == dom::MutationEvent_Binding::ADDITION) { + AddDependentIDsFor(accessible, aAttribute); + } +} + +void DocAccessible::ARIAAttributeDefaultWillChange(dom::Element* aElement, + nsAtom* aAttribute, + int32_t aModType) { + NS_ASSERTION(!IsDefunct(), + "Attribute changed called on defunct document accessible!"); + + if (aElement->HasAttr(aAttribute)) { + return; + } + + AttributeWillChange(aElement, kNameSpaceID_None, aAttribute, aModType); +} + +void DocAccessible::ARIAAttributeDefaultChanged(dom::Element* aElement, + nsAtom* aAttribute, + int32_t aModType) { + NS_ASSERTION(!IsDefunct(), + "Attribute changed called on defunct document accessible!"); + + if (aElement->HasAttr(aAttribute)) { + return; + } + + AttributeChanged(aElement, kNameSpaceID_None, aAttribute, aModType, nullptr); +} + +void DocAccessible::ARIAActiveDescendantChanged(LocalAccessible* aAccessible) { + if (dom::Element* elm = aAccessible->Elm()) { + nsAutoString id; + if (elm->GetAttr(nsGkAtoms::aria_activedescendant, id)) { + dom::Element* activeDescendantElm = IDRefsIterator::GetElem(elm, id); + if (activeDescendantElm) { + LocalAccessible* activeDescendant = GetAccessible(activeDescendantElm); + if (activeDescendant) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(activeDescendant, states::ACTIVE, true); + FireDelayedEvent(event); + if (aAccessible->IsActiveWidget()) { + FocusMgr()->ActiveItemChanged(activeDescendant, false); +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eFocus)) { + logging::ActiveItemChangeCausedBy("ARIA activedescedant changed", + activeDescendant); + } +#endif + } + return; + } + } + } + + // aria-activedescendant was cleared or changed to a non-existent node. + // Move focus back to the element itself if it has DOM focus. + if (aAccessible->IsActiveWidget()) { + FocusMgr()->ActiveItemChanged(aAccessible, false); +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eFocus)) { + logging::ActiveItemChangeCausedBy("ARIA activedescedant cleared", + aAccessible); + } +#endif + } + } +} + +void DocAccessible::ContentAppended(nsIContent* aFirstNewContent) { + MaybeHandleChangeToHiddenNameOrDescription(aFirstNewContent); +} + +void DocAccessible::ElementStateChanged(dom::Document* aDocument, + dom::Element* aElement, + dom::ElementState aStateMask) { + if (aStateMask.HasState(dom::ElementState::READWRITE) && + aElement == mDocumentNode->GetRootElement()) { + // This handles changes to designMode. contentEditable is handled by + // LocalAccessible::AttributeChangesState and + // LocalAccessible::DOMAttributeChanged. + const bool isEditable = + aElement->State().HasState(dom::ElementState::READWRITE); + RefPtr<AccEvent> event = + new AccStateChangeEvent(this, states::EDITABLE, isEditable); + FireDelayedEvent(event); + event = new AccStateChangeEvent(this, states::READONLY, !isEditable); + FireDelayedEvent(event); + } + + LocalAccessible* accessible = GetAccessible(aElement); + if (!accessible) return; + + if (aStateMask.HasState(dom::ElementState::CHECKED)) { + LocalAccessible* widget = accessible->ContainerWidget(); + if (widget && widget->IsSelect()) { + // Changing selection here changes what we cache for + // the viewport. + SetViewportCacheDirty(true); + AccSelChangeEvent::SelChangeType selChangeType = + aElement->State().HasState(dom::ElementState::CHECKED) + ? AccSelChangeEvent::eSelectionAdd + : AccSelChangeEvent::eSelectionRemove; + RefPtr<AccEvent> event = + new AccSelChangeEvent(widget, accessible, selChangeType); + FireDelayedEvent(event); + return; + } + + RefPtr<AccEvent> event = new AccStateChangeEvent( + accessible, states::CHECKED, + aElement->State().HasState(dom::ElementState::CHECKED)); + FireDelayedEvent(event); + } + + if (aStateMask.HasState(dom::ElementState::INVALID)) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(accessible, states::INVALID); + FireDelayedEvent(event); + } + + if (aStateMask.HasState(dom::ElementState::REQUIRED)) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(accessible, states::REQUIRED); + FireDelayedEvent(event); + } + + if (aStateMask.HasState(dom::ElementState::VISITED)) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(accessible, states::TRAVERSED, true); + FireDelayedEvent(event); + } + + // We only expose dom::ElementState::DEFAULT on buttons, but we can get + // notifications for other controls like checkboxes. + if (aStateMask.HasState(dom::ElementState::DEFAULT) && + accessible->IsButton()) { + RefPtr<AccEvent> event = + new AccStateChangeEvent(accessible, states::DEFAULT); + FireDelayedEvent(event); + } +} + +void DocAccessible::CharacterDataWillChange(nsIContent* aContent, + const CharacterDataChangeInfo&) {} + +void DocAccessible::CharacterDataChanged(nsIContent* aContent, + const CharacterDataChangeInfo&) {} + +void DocAccessible::ContentInserted(nsIContent* aChild) { + MaybeHandleChangeToHiddenNameOrDescription(aChild); +} + +void DocAccessible::ContentRemoved(nsIContent* aChildNode, + nsIContent* aPreviousSiblingNode) { +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eTree)) { + logging::MsgBegin("TREE", "DOM content removed; doc: %p", this); + logging::Node("container node", aChildNode->GetParent()); + logging::Node("content node", aChildNode); + logging::MsgEnd(); + } +#endif + ContentRemoved(aChildNode); +} + +void DocAccessible::ParentChainChanged(nsIContent* aContent) {} + +//////////////////////////////////////////////////////////////////////////////// +// LocalAccessible + +#ifdef A11Y_LOG +nsresult DocAccessible::HandleAccEvent(AccEvent* aEvent) { + if (logging::IsEnabled(logging::eDocLoad)) { + logging::DocLoadEventHandled(aEvent); + } + + return HyperTextAccessible::HandleAccEvent(aEvent); +} +#endif + +//////////////////////////////////////////////////////////////////////////////// +// Public members + +nsPresContext* DocAccessible::PresContext() const { + return mPresShell->GetPresContext(); +} + +void* DocAccessible::GetNativeWindow() const { + if (!mPresShell) { + return nullptr; + } + + nsViewManager* vm = mPresShell->GetViewManager(); + if (!vm) return nullptr; + + nsCOMPtr<nsIWidget> widget = vm->GetRootWidget(); + if (widget) return widget->GetNativeData(NS_NATIVE_WINDOW); + + return nullptr; +} + +LocalAccessible* DocAccessible::GetAccessibleByUniqueIDInSubtree( + void* aUniqueID) { + LocalAccessible* child = GetAccessibleByUniqueID(aUniqueID); + if (child) return child; + + uint32_t childDocCount = mChildDocuments.Length(); + for (uint32_t childDocIdx = 0; childDocIdx < childDocCount; childDocIdx++) { + DocAccessible* childDocument = mChildDocuments.ElementAt(childDocIdx); + child = childDocument->GetAccessibleByUniqueIDInSubtree(aUniqueID); + if (child) return child; + } + + return nullptr; +} + +LocalAccessible* DocAccessible::GetAccessibleOrContainer( + nsINode* aNode, bool aNoContainerIfPruned) const { + if (!aNode || !aNode->GetComposedDoc()) { + return nullptr; + } + + nsINode* start = aNode; + if (auto* shadowRoot = dom::ShadowRoot::FromNode(aNode)) { + // This can happen, for example, when called within + // SelectionManager::ProcessSelectionChanged due to focusing a direct + // child of a shadow root. + // GetFlattenedTreeParent works on children of a shadow root, but not the + // shadow root itself. + start = shadowRoot->GetHost(); + if (!start) { + return nullptr; + } + } + + for (nsINode* currNode : dom::InclusiveFlatTreeAncestors(*start)) { + // No container if is inside of aria-hidden subtree. + if (aNoContainerIfPruned && currNode->IsElement() && + aria::HasDefinedARIAHidden(currNode->AsElement())) { + return nullptr; + } + + // Check if node is in zero-sized map + if (aNoContainerIfPruned && currNode->IsHTMLElement(nsGkAtoms::map)) { + if (nsIFrame* frame = currNode->AsContent()->GetPrimaryFrame()) { + if (nsLayoutUtils::GetAllInFlowRectsUnion(frame, frame->GetParent()) + .IsEmpty()) { + return nullptr; + } + } + } + + if (LocalAccessible* accessible = GetAccessible(currNode)) { + return accessible; + } + } + + return nullptr; +} + +LocalAccessible* DocAccessible::GetContainerAccessible(nsINode* aNode) const { + return aNode ? GetAccessibleOrContainer(aNode->GetFlattenedTreeParentNode()) + : nullptr; +} + +LocalAccessible* DocAccessible::GetAccessibleOrDescendant( + nsINode* aNode) const { + LocalAccessible* acc = GetAccessible(aNode); + if (acc) return acc; + + if (aNode == mContent || aNode == mDocumentNode->GetRootElement()) { + // If the node is the doc's body or root element, return the doc accessible. + return const_cast<DocAccessible*>(this); + } + + acc = GetContainerAccessible(aNode); + if (acc) { + TreeWalker walker(acc, aNode->AsContent(), + TreeWalker::eWalkCache | TreeWalker::eScoped); + return walker.Next(); + } + + return nullptr; +} + +void DocAccessible::BindToDocument(LocalAccessible* aAccessible, + const nsRoleMapEntry* aRoleMapEntry) { + // Put into DOM node cache. + if (aAccessible->IsNodeMapEntry()) { + mNodeToAccessibleMap.InsertOrUpdate(aAccessible->GetNode(), aAccessible); + } + + // Put into unique ID cache. + mAccessibleCache.InsertOrUpdate(aAccessible->UniqueID(), RefPtr{aAccessible}); + + aAccessible->SetRoleMapEntry(aRoleMapEntry); + + if (aAccessible->HasOwnContent()) { + AddDependentIDsFor(aAccessible); + + nsIContent* content = aAccessible->GetContent(); + if (content->IsElement() && + content->AsElement()->HasAttr(nsGkAtoms::aria_owns)) { + mNotificationController->ScheduleRelocation(aAccessible); + } + } + + if (mIPCDoc) { + mInsertedAccessibles.EnsureInserted(aAccessible); + } + + QueueCacheUpdateForDependentRelations(aAccessible); +} + +void DocAccessible::UnbindFromDocument(LocalAccessible* aAccessible) { + NS_ASSERTION(mAccessibleCache.GetWeak(aAccessible->UniqueID()), + "Unbinding the unbound accessible!"); + + // Fire focus event on accessible having DOM focus if last focus was removed + // from the tree. + if (FocusMgr()->WasLastFocused(aAccessible)) { + FocusMgr()->ActiveItemChanged(nullptr); +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eFocus)) { + logging::ActiveItemChangeCausedBy("tree shutdown", aAccessible); + } +#endif + } + + // Remove an accessible from node-to-accessible map if it exists there. + if (aAccessible->IsNodeMapEntry() && + mNodeToAccessibleMap.Get(aAccessible->GetNode()) == aAccessible) { + mNodeToAccessibleMap.Remove(aAccessible->GetNode()); + } + + aAccessible->mStateFlags |= eIsNotInDocument; + + // Update XPCOM part. + xpcAccessibleDocument* xpcDoc = GetAccService()->GetCachedXPCDocument(this); + if (xpcDoc) xpcDoc->NotifyOfShutdown(aAccessible); + + void* uniqueID = aAccessible->UniqueID(); + + NS_ASSERTION(!aAccessible->IsDefunct(), "Shutdown the shutdown accessible!"); + aAccessible->Shutdown(); + + mAccessibleCache.Remove(uniqueID); +} + +void DocAccessible::ContentInserted(nsIContent* aStartChildNode, + nsIContent* aEndChildNode) { + // Ignore content insertions until we constructed accessible tree. Otherwise + // schedule tree update on content insertion after layout. + if (!mNotificationController || !HasLoadState(eTreeConstructed)) { + return; + } + + // The frame constructor guarantees that only ranges with the same parent + // arrive here in presence of dynamic changes to the page, see + // nsCSSFrameConstructor::IssueSingleInsertNotifications' callers. + nsINode* parent = aStartChildNode->GetFlattenedTreeParentNode(); + if (!parent) { + return; + } + + LocalAccessible* container = AccessibleOrTrueContainer(parent); + if (!container) { + return; + } + + AutoTArray<nsCOMPtr<nsIContent>, 10> list; + for (nsIContent* node = aStartChildNode; node != aEndChildNode; + node = node->GetNextSibling()) { + MOZ_ASSERT(parent == node->GetFlattenedTreeParentNode()); + if (PruneOrInsertSubtree(node)) { + list.AppendElement(node); + } + } + + mNotificationController->ScheduleContentInsertion(container, list); +} + +void DocAccessible::ScheduleTreeUpdate(nsIContent* aContent) { + if (mPendingUpdates.Contains(aContent)) { + return; + } + mPendingUpdates.AppendElement(aContent); + mNotificationController->ScheduleProcessing(); +} + +void DocAccessible::ProcessPendingUpdates() { + auto updates = std::move(mPendingUpdates); + for (auto update : updates) { + if (update->GetComposedDoc() != mDocumentNode) { + continue; + } + // The pruning logic will take care of avoiding unnecessary notifications. + ContentInserted(update, update->GetNextSibling()); + } +} + +bool DocAccessible::PruneOrInsertSubtree(nsIContent* aRoot) { + bool insert = false; + + // In the case that we are, or are in, a shadow host, we need to assure + // some accessibles are removed if they are not rendered anymore. + nsIContent* shadowHost = + aRoot->GetShadowRoot() ? aRoot : aRoot->GetContainingShadowHost(); + if (shadowHost) { + // Check all explicit children in the host, if they are not slotted + // then remove their accessibles and subtrees. + for (nsIContent* childNode = shadowHost->GetFirstChild(); childNode; + childNode = childNode->GetNextSibling()) { + if (!childNode->GetPrimaryFrame() && + !nsCoreUtils::CanCreateAccessibleWithoutFrame(childNode)) { + ContentRemoved(childNode); + } + } + + // If this is a slot, check to see if its fallback content is rendered, + // if not - remove it. + if (aRoot->IsHTMLElement(nsGkAtoms::slot)) { + for (nsIContent* childNode = aRoot->GetFirstChild(); childNode; + childNode = childNode->GetNextSibling()) { + if (!childNode->GetPrimaryFrame() && + !nsCoreUtils::CanCreateAccessibleWithoutFrame(childNode)) { + ContentRemoved(childNode); + } + } + } + } + + // If we already have an accessible, check if we need to remove it, recreate + // it, or keep it in place. + LocalAccessible* acc = GetAccessible(aRoot); + if (acc) { + MOZ_ASSERT(aRoot == acc->GetContent(), + "LocalAccessible has differing content!"); +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eTree)) { + logging::MsgBegin( + "TREE", "inserted content already has accessible; doc: %p", this); + logging::Node("content node", aRoot); + logging::AccessibleInfo("accessible node", acc); + logging::MsgEnd(); + } +#endif + + nsIFrame* frame = acc->GetFrame(); + if (frame) { + acc->MaybeQueueCacheUpdateForStyleChanges(); + } + + // LocalAccessible has no frame and it's not display:contents. Remove it. + // As well as removing the a11y subtree, we must also remove Accessibles + // for DOM descendants, since some of these might be relocated Accessibles + // and their DOM nodes are now hidden as well. + if (!frame && !nsCoreUtils::CanCreateAccessibleWithoutFrame(aRoot)) { + ContentRemoved(aRoot); + return false; + } + + // If the frame is hidden because its ancestor is specified with + // `content-visibility: hidden`, remove its Accessible. + if (frame && frame->IsHiddenByContentVisibilityOnAnyAncestor( + nsIFrame::IncludeContentVisibility::Hidden)) { + ContentRemoved(aRoot); + return false; + } + + // If it's a XULLabel it was probably reframed because a `value` attribute + // was added. The accessible creates its text leaf upon construction, so we + // need to recreate. Remove it, and schedule for reconstruction. + if (acc->IsXULLabel()) { + ContentRemoved(acc); + return true; + } + + // It is a broken image that is being reframed because it either got + // or lost an `alt` tag that would rerender this node as text. + if (frame && (acc->IsImage() != (frame->AccessibleType() == eImageType))) { + ContentRemoved(aRoot); + return true; + } + + // If the frame is an OuterDoc frame but this isn't an OuterDocAccessible, + // we need to recreate the LocalAccessible. This can happen for embed or + // object elements if their embedded content changes to be web content. + if (frame && !acc->IsOuterDoc() && + frame->AccessibleType() == eOuterDocType) { + ContentRemoved(aRoot); + return true; + } + + // If the content is focused, and is being re-framed, reset the selection + // listener for the node because the previous selection listener is on the + // old frame. + if (aRoot->IsElement() && FocusMgr()->HasDOMFocus(aRoot)) { + SelectionMgr()->SetControlSelectionListener(aRoot->AsElement()); + } + + // If the accessible is a table, or table part, its layout table + // status may have changed. We need to invalidate the associated + // mac table cache, which listens for the following event. We don't + // use this cache when the core cache is enabled, so to minimise event + // traffic only fire this event when that cache is off. + if (acc->IsTable() || acc->IsTableRow() || acc->IsTableCell()) { + LocalAccessible* table = nsAccUtils::TableFor(acc); + if (table && table->IsTable()) { + QueueCacheUpdate(table, CacheDomain::Table); + } + } + + // The accessible can be reparented or reordered in its parent. + // We schedule it for reinsertion. For example, a slotted element + // can change its slot attribute to a different slot. + insert = true; + + // If the frame is invisible, remove it. + // Normally, layout sends explicit a11y notifications for visibility + // changes (see SendA11yNotifications in RestyleManager). However, if a + // visibility change also reconstructs the frame, we must handle it here. + if (frame && !frame->StyleVisibility()->IsVisible()) { + ContentRemoved(aRoot); + // There might be visible descendants, so we want to walk the subtree. + // However, we know we don't want to reinsert this node, so we set insert + // to false. + insert = false; + } + } else { + // If there is no current accessible, and the node has a frame, or is + // display:contents, schedule it for insertion. + if (aRoot->GetPrimaryFrame() || + nsCoreUtils::CanCreateAccessibleWithoutFrame(aRoot)) { + // This may be a new subtree, the insertion process will recurse through + // its descendants. + if (!GetAccessibleOrDescendant(aRoot)) { + return true; + } + + // Content is not an accessible, but has accessible descendants. + // We schedule this container for insertion strictly for the case where it + // itself now needs an accessible. We will still need to recurse into the + // descendant content to prune accessibles, and in all likelyness to + // insert accessibles since accessible insertions will likeley get missed + // in an existing subtree. + insert = true; + } + } + + if (LocalAccessible* container = AccessibleOrTrueContainer(aRoot)) { + AutoTArray<nsCOMPtr<nsIContent>, 10> list; + dom::AllChildrenIterator iter = + dom::AllChildrenIterator(aRoot, nsIContent::eAllChildren, true); + while (nsIContent* childNode = iter.GetNextChild()) { + if (PruneOrInsertSubtree(childNode)) { + list.AppendElement(childNode); + } + } + + if (!list.IsEmpty()) { + mNotificationController->ScheduleContentInsertion(container, list); + } + } + + return insert; +} + +void DocAccessible::RecreateAccessible(nsIContent* aContent) { +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eTree)) { + logging::MsgBegin("TREE", "accessible recreated"); + logging::Node("content", aContent); + logging::MsgEnd(); + } +#endif + + // XXX: we shouldn't recreate whole accessible subtree, instead we should + // subclass hide and show events to handle them separately and implement their + // coalescence with normal hide and show events. Note, in this case they + // should be coalesced with normal show/hide events. + ContentRemoved(aContent); + ContentInserted(aContent, aContent->GetNextSibling()); +} + +void DocAccessible::ProcessInvalidationList() { + // Invalidate children of container accessible for each element in + // invalidation list. Allow invalidation list insertions while container + // children are recached. + for (uint32_t idx = 0; idx < mInvalidationList.Length(); idx++) { + nsIContent* content = mInvalidationList[idx]; + if (!HasAccessible(content) && content->HasID()) { + LocalAccessible* container = GetContainerAccessible(content); + if (container) { + // Check if the node is a target of aria-owns, and if so, don't process + // it here and let DoARIAOwnsRelocation process it. + AttrRelProviders* list = GetRelProviders( + content->AsElement(), nsDependentAtomString(content->GetID())); + bool shouldProcess = !!list; + if (shouldProcess) { + for (uint32_t idx = 0; idx < list->Length(); idx++) { + if (list->ElementAt(idx)->mRelAttr == nsGkAtoms::aria_owns) { + shouldProcess = false; + break; + } + } + + if (shouldProcess) { + ProcessContentInserted(container, content); + } + } + } + } + } + + mInvalidationList.Clear(); +} + +void DocAccessible::ProcessQueuedCacheUpdates() { + AUTO_PROFILER_MARKER_TEXT("DocAccessible::ProcessQueuedCacheUpdates", A11Y, + {}, ""_ns); + // DO NOT ADD CODE ABOVE THIS BLOCK: THIS CODE IS MEASURING TIMINGS. + + nsTArray<CacheData> data; + for (auto iter = mQueuedCacheUpdates.Iter(); !iter.Done(); iter.Next()) { + LocalAccessible* acc = iter.Key(); + uint64_t domain = iter.UserData(); + if (acc && acc->IsInDocument() && !acc->IsDefunct()) { + RefPtr<AccAttributes> fields = + acc->BundleFieldsForCache(domain, CacheUpdateType::Update); + + if (fields->Count()) { + data.AppendElement(CacheData( + acc->IsDoc() ? 0 : reinterpret_cast<uint64_t>(acc->UniqueID()), + fields)); + } + } + } + + mQueuedCacheUpdates.Clear(); + + if (mViewportCacheDirty) { + RefPtr<AccAttributes> fields = + BundleFieldsForCache(CacheDomain::Viewport, CacheUpdateType::Update); + if (fields->Count()) { + data.AppendElement(CacheData(0, fields)); + } + mViewportCacheDirty = false; + } + + if (data.Length()) { + IPCDoc()->SendCache(CacheUpdateType::Update, data); + } +} + +void DocAccessible::SendAccessiblesWillMove() { + if (!mIPCDoc) { + return; + } + nsTArray<uint64_t> ids; + for (LocalAccessible* acc : mMovedAccessibles) { + // If acc is defunct or not in a document, it was removed after it was + // moved. + if (!acc->IsDefunct() && acc->IsInDocument()) { + ids.AppendElement(reinterpret_cast<uintptr_t>(acc->UniqueID())); + // acc might have been re-parented. Since we cache bounds relative to the + // parent, we need to update the cache. + QueueCacheUpdate(acc, CacheDomain::Bounds); + } + } + if (!ids.IsEmpty()) { + mIPCDoc->SendAccessiblesWillMove(ids); + } +} + +LocalAccessible* DocAccessible::GetAccessibleEvenIfNotInMap( + nsINode* aNode) const { + if (!aNode->IsContent() || + !aNode->AsContent()->IsHTMLElement(nsGkAtoms::area)) { + return GetAccessible(aNode); + } + + // XXX Bug 135040, incorrect when multiple images use the same map. + nsIFrame* frame = aNode->AsContent()->GetPrimaryFrame(); + nsImageFrame* imageFrame = do_QueryFrame(frame); + if (imageFrame) { + LocalAccessible* parent = GetAccessible(imageFrame->GetContent()); + if (parent) { + if (HTMLImageMapAccessible* imageMap = parent->AsImageMap()) { + return imageMap->GetChildAccessibleFor(aNode); + } + return nullptr; + } + } + + return GetAccessible(aNode); +} + +//////////////////////////////////////////////////////////////////////////////// +// Protected members + +void DocAccessible::NotifyOfLoading(bool aIsReloading) { + // Mark the document accessible as loading, if it stays alive then we'll mark + // it as loaded when we receive proper notification. + mLoadState &= ~eDOMLoaded; + + if (!IsLoadEventTarget()) return; + + if (aIsReloading && !mLoadEventType && + // We can't fire events on a document whose tree isn't constructed yet. + HasLoadState(eTreeConstructed)) { + // Fire reload and state busy events on existing document accessible while + // event from user input flag can be calculated properly and accessible + // is alive. When new document gets loaded then this one is destroyed. + RefPtr<AccEvent> reloadEvent = + new AccEvent(nsIAccessibleEvent::EVENT_DOCUMENT_RELOAD, this); + nsEventShell::FireEvent(reloadEvent); + } + + // Fire state busy change event. Use delayed event since we don't care + // actually if event isn't delivered when the document goes away like a shot. + RefPtr<AccEvent> stateEvent = + new AccStateChangeEvent(this, states::BUSY, true); + FireDelayedEvent(stateEvent); +} + +void DocAccessible::DoInitialUpdate() { + AUTO_PROFILER_MARKER_TEXT("DocAccessible::DoInitialUpdate", A11Y, {}, ""_ns); + // DO NOT ADD CODE ABOVE THIS BLOCK: THIS CODE IS MEASURING TIMINGS. + + if (nsCoreUtils::IsTopLevelContentDocInProcess(mDocumentNode)) { + mDocFlags |= eTopLevelContentDocInProcess; + if (IPCAccessibilityActive()) { + nsIDocShell* docShell = mDocumentNode->GetDocShell(); + if (RefPtr<dom::BrowserChild> browserChild = + dom::BrowserChild::GetFrom(docShell)) { + // In content processes, top level content documents are always + // RootAccessibles. + MOZ_ASSERT(IsRoot()); + DocAccessibleChild* ipcDoc = IPCDoc(); + if (ipcDoc) { + browserChild->SetTopLevelDocAccessibleChild(ipcDoc); + } else { + ipcDoc = new DocAccessibleChild(this, browserChild); + SetIPCDoc(ipcDoc); + // Subsequent initialization might depend on being able to get the + // top level DocAccessibleChild, so set that as early as possible. + browserChild->SetTopLevelDocAccessibleChild(ipcDoc); + + browserChild->SendPDocAccessibleConstructor( + ipcDoc, nullptr, 0, mDocumentNode->GetBrowsingContext()); +#if !defined(XP_WIN) + ipcDoc->SendPDocAccessiblePlatformExtConstructor(); +#endif + } + } + } + } + + mLoadState |= eTreeConstructed; + + // Set up a root element and ARIA role mapping. + UpdateRootElIfNeeded(); + + // Build initial tree. + CacheChildrenInSubtree(this); +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eVerbose)) { + logging::Tree("TREE", "Initial subtree", this); + } + if (logging::IsEnabled(logging::eTreeSize)) { + logging::TreeSize("TREE SIZE", "Initial subtree", this); + } +#endif + + // Fire reorder event after the document tree is constructed. Note, since + // this reorder event is processed by parent document then events targeted to + // this document may be fired prior to this reorder event. If this is + // a problem then consider to keep event processing per tab document. + if (!IsRoot()) { + RefPtr<AccReorderEvent> reorderEvent = new AccReorderEvent(LocalParent()); + ParentDocument()->FireDelayedEvent(reorderEvent); + } + + if (ipc::ProcessChild::ExpectingShutdown()) { + return; + } + if (IPCAccessibilityActive()) { + DocAccessibleChild* ipcDoc = IPCDoc(); + MOZ_ASSERT(ipcDoc); + if (ipcDoc) { + // Send an initial update for this document and its attributes. Each acc + // contained in this doc will have its initial update sent in + // `InsertIntoIpcTree`. + SendCache(CacheDomain::All, CacheUpdateType::Initial); + + for (auto idx = 0U; idx < mChildren.Length(); idx++) { + ipcDoc->InsertIntoIpcTree(mChildren.ElementAt(idx), true); + } + } + } +} + +void DocAccessible::ProcessLoad() { + mLoadState |= eCompletelyLoaded; + +#ifdef A11Y_LOG + if (logging::IsEnabled(logging::eDocLoad)) { + logging::DocCompleteLoad(this, IsLoadEventTarget()); + } +#endif + + // Do not fire document complete/stop events for root chrome document + // accessibles and for frame/iframe documents because + // a) screen readers start working on focus event in the case of root chrome + // documents + // b) document load event on sub documents causes screen readers to act is if + // entire page is reloaded. + if (!IsLoadEventTarget()) return; + + // Fire complete/load stopped if the load event type is given. + if (mLoadEventType) { + RefPtr<AccEvent> loadEvent = new AccEvent(mLoadEventType, this); + FireDelayedEvent(loadEvent); + + mLoadEventType = 0; + } + + // Fire busy state change event. + RefPtr<AccEvent> stateEvent = + new AccStateChangeEvent(this, states::BUSY, false); + FireDelayedEvent(stateEvent); +} + +void DocAccessible::AddDependentIDsFor(LocalAccessible* aRelProvider, + nsAtom* aRelAttr) { + dom::Element* relProviderEl = aRelProvider->Elm(); + if (!relProviderEl) return; + + for (uint32_t idx = 0; idx < kRelationAttrsLen; idx++) { + nsStaticAtom* relAttr = kRelationAttrs[idx]; + if (aRelAttr && aRelAttr != relAttr) continue; + + if (relAttr == nsGkAtoms::_for) { + if (!relProviderEl->IsAnyOfHTMLElements(nsGkAtoms::label, + nsGkAtoms::output)) { + continue; + } + + } else if (relAttr == nsGkAtoms::control) { + if (!relProviderEl->IsAnyOfXULElements(nsGkAtoms::label, + nsGkAtoms::description)) { + continue; + } + } + + IDRefsIterator iter(this, relProviderEl, relAttr); + while (true) { + const nsDependentSubstring id = iter.NextID(); + if (id.IsEmpty()) break; + + AttrRelProviders* providers = GetOrCreateRelProviders(relProviderEl, id); + if (providers) { + AttrRelProvider* provider = new AttrRelProvider(relAttr, relProviderEl); + if (provider) { + providers->AppendElement(provider); + + // We've got here during the children caching. If the referenced + // content is not accessible then store it to pend its container + // children invalidation (this happens immediately after the caching + // is finished). + nsIContent* dependentContent = iter.GetElem(id); + if (dependentContent) { + if (!HasAccessible(dependentContent)) { + mInvalidationList.AppendElement(dependentContent); + } + } + } + } + } + + // If the relation attribute is given then we don't have anything else to + // check. + if (aRelAttr) break; + } + + // Make sure to schedule the tree update if needed. + mNotificationController->ScheduleProcessing(); +} + +void DocAccessible::RemoveDependentIDsFor(LocalAccessible* aRelProvider, + nsAtom* aRelAttr) { + dom::Element* relProviderElm = aRelProvider->Elm(); + if (!relProviderElm) return; + + for (uint32_t idx = 0; idx < kRelationAttrsLen; idx++) { + nsStaticAtom* relAttr = kRelationAttrs[idx]; + if (aRelAttr && aRelAttr != kRelationAttrs[idx]) continue; + + IDRefsIterator iter(this, relProviderElm, relAttr); + while (true) { + const nsDependentSubstring id = iter.NextID(); + if (id.IsEmpty()) break; + + AttrRelProviders* providers = GetRelProviders(relProviderElm, id); + if (providers) { + providers->RemoveElementsBy( + [relAttr, relProviderElm](const auto& provider) { + return provider->mRelAttr == relAttr && + provider->mContent == relProviderElm; + }); + + RemoveRelProvidersIfEmpty(relProviderElm, id); + } + } + + // If the relation attribute is given then we don't have anything else to + // check. + if (aRelAttr) break; + } +} + +bool DocAccessible::UpdateAccessibleOnAttrChange(dom::Element* aElement, + nsAtom* aAttribute) { + if (aAttribute == nsGkAtoms::role) { + // It is common for js libraries to set the role on the body element after + // the document has loaded. In this case we just update the role map entry. + if (mContent == aElement) { + SetRoleMapEntryForDoc(aElement); + if (mIPCDoc) { + mIPCDoc->SendRoleChangedEvent(Role(), mRoleMapEntryIndex); + } + + return true; + } + + // Recreate the accessible when role is changed because we might require a + // different accessible class for the new role or the accessible may expose + // a different sets of interfaces (COM restriction). + RecreateAccessible(aElement); + + return true; + } + + if (aAttribute == nsGkAtoms::multiple) { + if (dom::HTMLSelectElement* select = + dom::HTMLSelectElement::FromNode(aElement)) { + if (select->Size() <= 1) { + // Adding the 'multiple' attribute to a select that has a size of 1 + // creates a listbox as opposed to a combobox with a popup combobox + // list. Removing the attribute does the opposite. + RecreateAccessible(aElement); + return true; + } + } + } + + if (aAttribute == nsGkAtoms::size && + aElement->IsHTMLElement(nsGkAtoms::select)) { + // Changing the size of a select element can potentially change it from a + // combobox button to a listbox with different underlying implementations. + RecreateAccessible(aElement); + return true; + } + + if (aAttribute == nsGkAtoms::type) { + // If the input[type] changes, we should recreate the accessible. + RecreateAccessible(aElement); + return true; + } + + if (aElement->IsHTMLElement(nsGkAtoms::img) && aAttribute == nsGkAtoms::alt) { + // If alt text changes on an img element, we may want to create or remove an + // accessible for that img. + if (nsAccessibilityService::ShouldCreateImgAccessible(aElement, this)) { + if (GetAccessible(aElement)) { + // If the accessible already exists, there's no need to create one. + return false; + } + ContentInserted(aElement, aElement->GetNextSibling()); + } else { + ContentRemoved(aElement); + } + return true; + } + + return false; +} + +void DocAccessible::UpdateRootElIfNeeded() { + dom::Element* rootEl = mDocumentNode->GetBodyElement(); + if (!rootEl) { + rootEl = mDocumentNode->GetRootElement(); + } + if (rootEl != mContent) { + mContent = rootEl; + SetRoleMapEntryForDoc(rootEl); + if (mIPCDoc) { + mIPCDoc->SendRoleChangedEvent(Role(), mRoleMapEntryIndex); + } + } +} + +/** + * Content insertion helper. + */ +class InsertIterator final { + public: + InsertIterator(LocalAccessible* aContext, + const nsTArray<nsCOMPtr<nsIContent>>* aNodes) + : mChild(nullptr), + mChildBefore(nullptr), + mWalker(aContext), + mNodes(aNodes), + mNodesIdx(0) { + MOZ_ASSERT(aContext, "No context"); + MOZ_ASSERT(aNodes, "No nodes to search for accessible elements"); + MOZ_COUNT_CTOR(InsertIterator); + } + MOZ_COUNTED_DTOR(InsertIterator) + + LocalAccessible* Context() const { return mWalker.Context(); } + LocalAccessible* Child() const { return mChild; } + LocalAccessible* ChildBefore() const { return mChildBefore; } + DocAccessible* Document() const { return mWalker.Document(); } + + /** + * Iterates to a next accessible within the inserted content. + */ + bool Next(); + + void Rejected() { + mChild = nullptr; + mChildBefore = nullptr; + } + + private: + LocalAccessible* mChild; + LocalAccessible* mChildBefore; + TreeWalker mWalker; + + const nsTArray<nsCOMPtr<nsIContent>>* mNodes; + nsTHashSet<nsPtrHashKey<const nsIContent>> mProcessedNodes; + uint32_t mNodesIdx; +}; + +bool InsertIterator::Next() { + if (mNodesIdx > 0) { + // If we already processed the first node in the mNodes list, + // check if we can just use the walker to get its next sibling. + LocalAccessible* nextChild = mWalker.Next(); + if (nextChild) { + mChildBefore = mChild; + mChild = nextChild; + return true; + } + } + + while (mNodesIdx < mNodes->Length()) { + nsIContent* node = mNodes->ElementAt(mNodesIdx++); + // Check to see if we already processed this node with this iterator. + // this can happen if we get two redundant insertions in the case of a + // text and frame insertion. + if (!mProcessedNodes.EnsureInserted(node)) { + continue; + } + + LocalAccessible* container = Document()->AccessibleOrTrueContainer( + node->GetFlattenedTreeParentNode(), true); + // Ignore nodes that are not contained by the container anymore. + // The container might be changed, for example, because of the subsequent + // overlapping content insertion (i.e. other content was inserted between + // this inserted content and its container or the content was reinserted + // into different container of unrelated part of tree). To avoid a double + // processing of the content insertion ignore this insertion notification. + // Note, the inserted content might be not in tree at all at this point + // what means there's no container. Ignore the insertion too. + if (container != Context()) { + continue; + } + + // HTML comboboxes have no-content list accessible as an intermediate + // containing all options. + if (container->IsHTMLCombobox()) { + container = container->LocalFirstChild(); + } + + if (!container->IsAcceptableChild(node)) { + continue; + } + +#ifdef A11Y_LOG + logging::TreeInfo("traversing an inserted node", logging::eVerbose, + "container", container, "node", node); +#endif + + nsIContent* prevNode = mChild ? mChild->GetContent() : nullptr; + if (prevNode && prevNode->GetNextSibling() == node) { + // If inserted nodes are siblings then just move the walker next. + LocalAccessible* nextChild = mWalker.Scope(node); + if (nextChild) { + mChildBefore = mChild; + mChild = nextChild; + return true; + } + } else { + // Otherwise use a new walker to find this node in the container's + // subtree, and retrieve its preceding sibling. + TreeWalker finder(container); + if (finder.Seek(node)) { + mChild = mWalker.Scope(node); + if (mChild) { + MOZ_ASSERT(!mChild->IsRelocated(), "child cannot be aria owned"); + mChildBefore = finder.Prev(); + return true; + } + } + } + } + + return false; +} + +void DocAccessible::ProcessContentInserted( + LocalAccessible* aContainer, const nsTArray<nsCOMPtr<nsIContent>>* aNodes) { + // Process insertions if the container accessible is still in tree. + if (!aContainer->IsInDocument()) { + return; + } + + // If new root content has been inserted then update it. + if (aContainer == this) { + UpdateRootElIfNeeded(); + } + + InsertIterator iter(aContainer, aNodes); + if (!iter.Next()) { + return; + } + +#ifdef A11Y_LOG + logging::TreeInfo("children before insertion", logging::eVerbose, aContainer); +#endif + + TreeMutation mt(aContainer); + do { + LocalAccessible* parent = iter.Child()->LocalParent(); + if (parent) { + LocalAccessible* previousSibling = iter.ChildBefore(); + if (parent != aContainer || + iter.Child()->LocalPrevSibling() != previousSibling) { + if (previousSibling && previousSibling->LocalParent() != aContainer) { + // previousSibling hasn't been moved into aContainer yet. + // previousSibling should be later in the insertion list, so the tree + // will get adjusted when we process it later. + MOZ_DIAGNOSTIC_ASSERT(parent == aContainer, + "Child moving to new parent, but previous " + "sibling in wrong parent"); + continue; + } +#ifdef A11Y_LOG + logging::TreeInfo("relocating accessible", 0, "old parent", parent, + "new parent", aContainer, "child", iter.Child(), + nullptr); +#endif + MoveChild(iter.Child(), aContainer, + previousSibling ? previousSibling->IndexInParent() + 1 : 0); + } + continue; + } + + if (aContainer->InsertAfter(iter.Child(), iter.ChildBefore())) { +#ifdef A11Y_LOG + logging::TreeInfo("accessible was inserted", 0, "container", aContainer, + "child", iter.Child(), nullptr); +#endif + + CreateSubtree(iter.Child()); + mt.AfterInsertion(iter.Child()); + continue; + } + + MOZ_ASSERT_UNREACHABLE("accessible was rejected"); + iter.Rejected(); + } while (iter.Next()); + + mt.Done(); + +#ifdef A11Y_LOG + logging::TreeInfo("children after insertion", logging::eVerbose, aContainer); +#endif + + FireEventsOnInsertion(aContainer); +} + +void DocAccessible::ProcessContentInserted(LocalAccessible* aContainer, + nsIContent* aNode) { + if (!aContainer->IsInDocument()) { + return; + } + +#ifdef A11Y_LOG + logging::TreeInfo("children before insertion", logging::eVerbose, aContainer); +#endif + +#ifdef A11Y_LOG + logging::TreeInfo("traversing an inserted node", logging::eVerbose, + "container", aContainer, "node", aNode); +#endif + + TreeWalker walker(aContainer); + if (aContainer->IsAcceptableChild(aNode) && walker.Seek(aNode)) { + LocalAccessible* child = GetAccessible(aNode); + if (!child) { + child = GetAccService()->CreateAccessible(aNode, aContainer); + } + + if (child) { + TreeMutation mt(aContainer); + if (!aContainer->InsertAfter(child, walker.Prev())) { + return; + } + CreateSubtree(child); + mt.AfterInsertion(child); + mt.Done(); + + FireEventsOnInsertion(aContainer); + } + } + +#ifdef A11Y_LOG + logging::TreeInfo("children after insertion", logging::eVerbose, aContainer); +#endif +} + +void DocAccessible::FireEventsOnInsertion(LocalAccessible* aContainer) { + // Check to see if change occurred inside an alert, and fire an EVENT_ALERT + // if it did. + if (aContainer->IsAlert() || aContainer->IsInsideAlert()) { + LocalAccessible* ancestor = aContainer; + do { + if (ancestor->IsAlert()) { + FireDelayedEvent(nsIAccessibleEvent::EVENT_ALERT, ancestor); + break; + } + } while ((ancestor = ancestor->LocalParent())); + } +} + +void DocAccessible::ContentRemoved(LocalAccessible* aChild) { + MOZ_DIAGNOSTIC_ASSERT(aChild != this, "Should never be called for the doc"); + LocalAccessible* parent = aChild->LocalParent(); + MOZ_DIAGNOSTIC_ASSERT(parent, "Unattached accessible from tree"); + +#ifdef A11Y_LOG + logging::TreeInfo("process content removal", 0, "container", parent, "child", + aChild, nullptr); +#endif + + // XXX: event coalescence may kill us + RefPtr<LocalAccessible> kungFuDeathGripChild(aChild); + + TreeMutation mt(parent); + mt.BeforeRemoval(aChild); + + if (aChild->IsDefunct()) { + MOZ_ASSERT_UNREACHABLE("Event coalescence killed the accessible"); + mt.Done(); + return; + } + + MOZ_DIAGNOSTIC_ASSERT(aChild->LocalParent(), "Alive but unparented #1"); + + if (aChild->IsRelocated()) { + nsTArray<RefPtr<LocalAccessible>>* owned = mARIAOwnsHash.Get(parent); + MOZ_ASSERT(owned, "IsRelocated flag is out of sync with mARIAOwnsHash"); + owned->RemoveElement(aChild); + if (owned->Length() == 0) { + mARIAOwnsHash.Remove(parent); + } + } + MOZ_DIAGNOSTIC_ASSERT(aChild->LocalParent(), "Unparented #2"); + UncacheChildrenInSubtree(aChild); + parent->RemoveChild(aChild); + + mt.Done(); +} + +void DocAccessible::ContentRemoved(nsIContent* aContentNode) { + if (!mRemovedNodes.EnsureInserted(aContentNode)) { + return; + } + + // If child node is not accessible then look for its accessible children. + LocalAccessible* acc = GetAccessible(aContentNode); + if (acc) { + ContentRemoved(acc); + } + + dom::AllChildrenIterator iter = + dom::AllChildrenIterator(aContentNode, nsIContent::eAllChildren, true); + while (nsIContent* childNode = iter.GetNextChild()) { + ContentRemoved(childNode); + } + + // If this node has a shadow root, remove its explicit children too. + // The host node may be removed after the shadow root was attached, and + // before we asynchronously prune the light DOM and construct the shadow DOM. + // If this is a case where the node does not have its own accessible, we will + // not recurse into its current children, so we need to use an + // ExplicitChildIterator in order to get its accessible children in the light + // DOM, since they are not accessible anymore via AllChildrenIterator. + if (aContentNode->GetShadowRoot()) { + for (nsIContent* childNode = aContentNode->GetFirstChild(); childNode; + childNode = childNode->GetNextSibling()) { + ContentRemoved(childNode); + } + } +} + +bool DocAccessible::RelocateARIAOwnedIfNeeded(nsIContent* aElement) { + if (!aElement->HasID()) return false; + + AttrRelProviders* list = GetRelProviders( + aElement->AsElement(), nsDependentAtomString(aElement->GetID())); + if (list) { + for (uint32_t idx = 0; idx < list->Length(); idx++) { + if (list->ElementAt(idx)->mRelAttr == nsGkAtoms::aria_owns) { + LocalAccessible* owner = GetAccessible(list->ElementAt(idx)->mContent); + if (owner) { + mNotificationController->ScheduleRelocation(owner); + return true; + } + } + } + } + + return false; +} + +void DocAccessible::DoARIAOwnsRelocation(LocalAccessible* aOwner) { + MOZ_ASSERT(aOwner, "aOwner must be a valid pointer"); + MOZ_ASSERT(aOwner->Elm(), "aOwner->Elm() must be a valid pointer"); + +#ifdef A11Y_LOG + logging::TreeInfo("aria owns relocation", logging::eVerbose, aOwner); +#endif + + nsTArray<RefPtr<LocalAccessible>>* owned = + mARIAOwnsHash.GetOrInsertNew(aOwner); + + IDRefsIterator iter(this, aOwner->Elm(), nsGkAtoms::aria_owns); + uint32_t idx = 0; + while (nsIContent* childEl = iter.NextElem()) { + LocalAccessible* child = GetAccessible(childEl); + auto insertIdx = aOwner->ChildCount() - owned->Length() + idx; + + // Make an attempt to create an accessible if it wasn't created yet. + if (!child) { + // An owned child cannot be an ancestor of the owner. + bool ok = true; + bool check = true; + for (LocalAccessible* parent = aOwner; parent && !parent->IsDoc(); + parent = parent->LocalParent()) { + if (check) { + if (parent->Elm()->IsInclusiveDescendantOf(childEl)) { + ok = false; + break; + } + } + // We need to do the DOM descendant check again whenever the DOM + // lineage changes. If parent is relocated, that means the next + // ancestor will have a different DOM lineage. + check = parent->IsRelocated(); + } + if (!ok) { + continue; + } + + if (aOwner->IsAcceptableChild(childEl)) { + child = GetAccService()->CreateAccessible(childEl, aOwner); + if (child) { + TreeMutation imut(aOwner); + aOwner->InsertChildAt(insertIdx, child); + imut.AfterInsertion(child); + imut.Done(); + + child->SetRelocated(true); + owned->InsertElementAt(idx, child); + idx++; + + // Create subtree before adjusting the insertion index, since subtree + // creation may alter children in the container. + CreateSubtree(child); + FireEventsOnInsertion(aOwner); + } + } + continue; + } + +#ifdef A11Y_LOG + logging::TreeInfo("aria owns traversal", logging::eVerbose, "candidate", + child, nullptr); +#endif + + if (owned->IndexOf(child) < idx) { + continue; // ignore second entry of same ID + } + + // Same child on same position, no change. + if (child->LocalParent() == aOwner) { + int32_t indexInParent = child->IndexInParent(); + + // The child is being placed in its current index, + // eg. aria-owns='id1 id2 id3' is changed to aria-owns='id3 id2 id1'. + if (indexInParent == static_cast<int32_t>(insertIdx)) { + MOZ_ASSERT(child->IsRelocated(), + "A child, having an index in parent from aria ownded " + "indices range, has to be aria owned"); + MOZ_ASSERT(owned->ElementAt(idx) == child, + "Unexpected child in ARIA owned array"); + idx++; + continue; + } + + // The child is being inserted directly after its current index, + // resulting in a no-move case. This will happen when a parent aria-owns + // its last ordinal child: + // <ul aria-owns='id2'><li id='id1'></li><li id='id2'></li></ul> + if (indexInParent == static_cast<int32_t>(insertIdx) - 1) { + MOZ_ASSERT(!child->IsRelocated(), + "Child should be in its ordinal position"); + child->SetRelocated(true); + owned->InsertElementAt(idx, child); + idx++; + continue; + } + } + + MOZ_ASSERT(owned->SafeElementAt(idx) != child, "Already in place!"); + + // A new child is found, check for loops. + if (child->LocalParent() != aOwner) { + // Child is aria-owned by another container, skip. + if (child->IsRelocated()) { + continue; + } + + LocalAccessible* parent = aOwner; + while (parent && parent != child && !parent->IsDoc()) { + parent = parent->LocalParent(); + } + // A referred child cannot be a parent of the owner. + if (parent == child) { + continue; + } + } + + if (MoveChild(child, aOwner, insertIdx)) { + child->SetRelocated(true); + MOZ_ASSERT(owned == mARIAOwnsHash.Get(aOwner)); + owned = mARIAOwnsHash.GetOrInsertNew(aOwner); + owned->InsertElementAt(idx, child); + idx++; + } + } + + // Put back children that are not seized anymore. + PutChildrenBack(owned, idx); + if (owned->Length() == 0) { + mARIAOwnsHash.Remove(aOwner); + } +} + +void DocAccessible::PutChildrenBack( + nsTArray<RefPtr<LocalAccessible>>* aChildren, uint32_t aStartIdx) { + MOZ_ASSERT(aStartIdx <= aChildren->Length(), "Wrong removal index"); + + for (auto idx = aStartIdx; idx < aChildren->Length(); idx++) { + LocalAccessible* child = aChildren->ElementAt(idx); + if (!child->IsInDocument()) { + continue; + } + + // Remove the child from the owner + LocalAccessible* owner = child->LocalParent(); + if (!owner) { + NS_ERROR("Cannot put the child back. No parent, a broken tree."); + continue; + } + +#ifdef A11Y_LOG + logging::TreeInfo("aria owns put child back", 0, "old parent", owner, + "child", child, nullptr); +#endif + + // Unset relocated flag to find an insertion point for the child. + child->SetRelocated(false); + + nsIContent* content = child->GetContent(); + int32_t idxInParent = -1; + LocalAccessible* origContainer = + AccessibleOrTrueContainer(content->GetFlattenedTreeParentNode()); + if (origContainer) { + TreeWalker walker(origContainer); + if (walker.Seek(content)) { + LocalAccessible* prevChild = walker.Prev(); + if (prevChild) { + idxInParent = prevChild->IndexInParent() + 1; + MOZ_DIAGNOSTIC_ASSERT(origContainer == prevChild->LocalParent(), + "Broken tree"); + origContainer = prevChild->LocalParent(); + } else { + idxInParent = 0; + } + } + } + + // The child may have already be in its ordinal place for 2 reasons: + // 1. It was the last ordinal child, and the first aria-owned child. + // given: <ul id="list" aria-owns="b"><li id="a"></li><li + // id="b"></li></ul> after load: $("list").setAttribute("aria-owns", ""); + // 2. The preceding adopted children were just reclaimed, eg: + // given: <ul id="list"><li id="b"></li></ul> + // after load: $("list").setAttribute("aria-owns", "a b"); + // later: $("list").setAttribute("aria-owns", ""); + if (origContainer != owner || child->IndexInParent() != idxInParent) { + DebugOnly<bool> moved = MoveChild(child, origContainer, idxInParent); + MOZ_ASSERT(moved, "Failed to put child back."); + } else { + MOZ_ASSERT(!child->LocalPrevSibling() || + !child->LocalPrevSibling()->IsRelocated(), + "No relocated child should appear before this one"); + MOZ_ASSERT(!child->LocalNextSibling() || + child->LocalNextSibling()->IsRelocated(), + "No ordinal child should appear after this one"); + } + } + + aChildren->RemoveLastElements(aChildren->Length() - aStartIdx); +} + +void DocAccessible::TrackMovedAccessible(LocalAccessible* aAcc) { + MOZ_ASSERT(aAcc->mDoc == this); + // If an Accessible is inserted and moved during the same tick, don't track + // it as a move because it hasn't been shown yet. + if (!mInsertedAccessibles.Contains(aAcc)) { + mMovedAccessibles.EnsureInserted(aAcc); + } + // When we move an Accessible, we're also moving its descendants. + if (aAcc->IsOuterDoc()) { + // Don't descend into other documents. + return; + } + for (uint32_t c = 0, count = aAcc->ContentChildCount(); c < count; ++c) { + TrackMovedAccessible(aAcc->ContentChildAt(c)); + } +} + +bool DocAccessible::MoveChild(LocalAccessible* aChild, + LocalAccessible* aNewParent, + int32_t aIdxInParent) { + MOZ_ASSERT(aChild, "No child"); + MOZ_ASSERT(aChild->LocalParent(), "No parent"); + // We can't guarantee MoveChild works correctly for accessibilities storing + // children outside mChildren. + MOZ_ASSERT( + aIdxInParent <= static_cast<int32_t>(aNewParent->mChildren.Length()), + "Wrong insertion point for a moving child"); + + LocalAccessible* curParent = aChild->LocalParent(); + + if (!aNewParent->IsAcceptableChild(aChild->GetContent())) { + return false; + } + +#ifdef A11Y_LOG + logging::TreeInfo("move child", 0, "old parent", curParent, "new parent", + aNewParent, "child", aChild, nullptr); +#endif + + // Forget aria-owns info in case of ARIA owned element. The caller is expected + // to update it if needed. + if (aChild->IsRelocated()) { + aChild->SetRelocated(false); + nsTArray<RefPtr<LocalAccessible>>* owned = mARIAOwnsHash.Get(curParent); + MOZ_ASSERT(owned, "IsRelocated flag is out of sync with mARIAOwnsHash"); + owned->RemoveElement(aChild); + if (owned->Length() == 0) { + mARIAOwnsHash.Remove(curParent); + } + } + + if (curParent == aNewParent) { + MOZ_ASSERT(aChild->IndexInParent() != aIdxInParent, "No move case"); + curParent->RelocateChild(aIdxInParent, aChild); + if (mIPCDoc) { + TrackMovedAccessible(aChild); + } + +#ifdef A11Y_LOG + logging::TreeInfo("move child: parent tree after", logging::eVerbose, + curParent); +#endif + return true; + } + + // If the child cannot be re-inserted into the tree, then make sure to remove + // it from its present parent and then shutdown it. + bool hasInsertionPoint = + (aIdxInParent >= 0) && + (aIdxInParent <= static_cast<int32_t>(aNewParent->mChildren.Length())); + + TreeMutation rmut(curParent); + rmut.BeforeRemoval(aChild, hasInsertionPoint && TreeMutation::kNoShutdown); + curParent->RemoveChild(aChild); + rmut.Done(); + + // No insertion point for the child. + if (!hasInsertionPoint) { + return true; + } + + TreeMutation imut(aNewParent); + aNewParent->InsertChildAt(aIdxInParent, aChild); + if (mIPCDoc) { + TrackMovedAccessible(aChild); + } + imut.AfterInsertion(aChild); + imut.Done(); + +#ifdef A11Y_LOG + logging::TreeInfo("move child: old parent tree after", logging::eVerbose, + curParent); + logging::TreeInfo("move child: new parent tree after", logging::eVerbose, + aNewParent); +#endif + + return true; +} + +void DocAccessible::CacheChildrenInSubtree(LocalAccessible* aRoot, + LocalAccessible** aFocusedAcc) { + // If the accessible is focused then report a focus event after all related + // mutation events. + if (aFocusedAcc && !*aFocusedAcc && + FocusMgr()->HasDOMFocus(aRoot->GetContent())) { + *aFocusedAcc = aRoot; + } + + LocalAccessible* root = + aRoot->IsHTMLCombobox() ? aRoot->LocalFirstChild() : aRoot; + if (root->KidsFromDOM()) { + TreeMutation mt(root, TreeMutation::kNoEvents); + TreeWalker walker(root); + while (LocalAccessible* child = walker.Next()) { + if (child->IsBoundToParent()) { + MoveChild(child, root, root->mChildren.Length()); + continue; + } + + root->AppendChild(child); + mt.AfterInsertion(child); + + CacheChildrenInSubtree(child, aFocusedAcc); + } + mt.Done(); + } + + // Fire events for ARIA elements. + if (!aRoot->HasARIARole()) { + return; + } + + // XXX: we should delay document load complete event if the ARIA document + // has aria-busy. + roles::Role role = aRoot->ARIARole(); + if (!aRoot->IsDoc() && + (role == roles::DIALOG || role == roles::NON_NATIVE_DOCUMENT)) { + FireDelayedEvent(nsIAccessibleEvent::EVENT_DOCUMENT_LOAD_COMPLETE, aRoot); + } +} + +void DocAccessible::UncacheChildrenInSubtree(LocalAccessible* aRoot) { + aRoot->mStateFlags |= eIsNotInDocument; + RemoveDependentIDsFor(aRoot); + + // The parent of the removed subtree is about to be cleared, so we must do + // this here rather than in LocalAccessible::UnbindFromParent because we need + // the ancestry for this to work. + if (aRoot->IsTable() || aRoot->IsTableCell()) { + CachedTableAccessible::Invalidate(aRoot); + } + + nsTArray<RefPtr<LocalAccessible>>* owned = mARIAOwnsHash.Get(aRoot); + uint32_t count = aRoot->ContentChildCount(); + for (uint32_t idx = 0; idx < count; idx++) { + LocalAccessible* child = aRoot->ContentChildAt(idx); + + if (child->IsRelocated()) { + MOZ_ASSERT(owned, "IsRelocated flag is out of sync with mARIAOwnsHash"); + owned->RemoveElement(child); + if (owned->Length() == 0) { + mARIAOwnsHash.Remove(aRoot); + owned = nullptr; + } + } + + // Removing this accessible from the document doesn't mean anything about + // accessibles for subdocuments, so skip removing those from the tree. + if (!child->IsDoc()) { + UncacheChildrenInSubtree(child); + } + } + + if (aRoot->IsNodeMapEntry() && + mNodeToAccessibleMap.Get(aRoot->GetNode()) == aRoot) { + mNodeToAccessibleMap.Remove(aRoot->GetNode()); + } +} + +void DocAccessible::ShutdownChildrenInSubtree(LocalAccessible* aAccessible) { + // Traverse through children and shutdown them before this accessible. When + // child gets shutdown then it removes itself from children array of its + // parent. Use jdx index to process the cases if child is not attached to the + // parent and as result doesn't remove itself from its children. + uint32_t count = aAccessible->ContentChildCount(); + for (uint32_t idx = 0, jdx = 0; idx < count; idx++) { + LocalAccessible* child = aAccessible->ContentChildAt(jdx); + if (!child->IsBoundToParent()) { + NS_ERROR("Parent refers to a child, child doesn't refer to parent!"); + jdx++; + } + + // Don't cross document boundaries. The outerdoc shutdown takes care about + // its subdocument. + if (!child->IsDoc()) ShutdownChildrenInSubtree(child); + } + + UnbindFromDocument(aAccessible); +} + +bool DocAccessible::IsLoadEventTarget() const { + nsCOMPtr<nsIDocShellTreeItem> treeItem = mDocumentNode->GetDocShell(); + if (!treeItem) { + return false; + } + + nsCOMPtr<nsIDocShellTreeItem> parentTreeItem; + treeItem->GetInProcessParent(getter_AddRefs(parentTreeItem)); + + // Not a root document. + if (parentTreeItem) { + // Return true if it's either: + // a) tab document; + nsCOMPtr<nsIDocShellTreeItem> rootTreeItem; + treeItem->GetInProcessRootTreeItem(getter_AddRefs(rootTreeItem)); + if (parentTreeItem == rootTreeItem) return true; + + // b) frame/iframe document and its parent document is not in loading state + // Note: we can get notifications while document is loading (and thus + // while there's no parent document yet). + DocAccessible* parentDoc = ParentDocument(); + return parentDoc && parentDoc->HasLoadState(eCompletelyLoaded); + } + + // It's content (not chrome) root document. + return (treeItem->ItemType() == nsIDocShellTreeItem::typeContent); +} + +void DocAccessible::SetIPCDoc(DocAccessibleChild* aIPCDoc) { + MOZ_ASSERT(!mIPCDoc || !aIPCDoc, "Clobbering an attached IPCDoc!"); + mIPCDoc = aIPCDoc; +} + +void DocAccessible::DispatchScrollingEvent(nsINode* aTarget, + uint32_t aEventType) { + LocalAccessible* acc = GetAccessible(aTarget); + if (!acc) { + return; + } + + nsIFrame* frame = acc->GetFrame(); + if (!frame) { + // Although the accessible had a frame at scroll time, it may now be gone + // because of display: contents. + return; + } + + auto [scrollPoint, scrollRange] = ComputeScrollData(acc); + + int32_t appUnitsPerDevPixel = + mPresShell->GetPresContext()->AppUnitsPerDevPixel(); + + LayoutDeviceIntPoint scrollPointDP = LayoutDevicePoint::FromAppUnitsToNearest( + scrollPoint, appUnitsPerDevPixel); + LayoutDeviceIntRect scrollRangeDP = + LayoutDeviceRect::FromAppUnitsToNearest(scrollRange, appUnitsPerDevPixel); + + RefPtr<AccEvent> event = + new AccScrollingEvent(aEventType, acc, scrollPointDP.x, scrollPointDP.y, + scrollRangeDP.width, scrollRangeDP.height); + nsEventShell::FireEvent(event); +} + +void DocAccessible::ARIAActiveDescendantIDMaybeMoved( + LocalAccessible* aAccessible) { + LocalAccessible* widget = nullptr; + if (aAccessible->IsActiveDescendant(&widget) && widget) { + // The active descendant might have just been inserted and may not be in the + // tree yet. Therefore, schedule this async to ensure the tree is up to + // date. + mNotificationController + ->ScheduleNotification<DocAccessible, LocalAccessible>( + this, &DocAccessible::ARIAActiveDescendantChanged, widget); + } +} + +void DocAccessible::SetRoleMapEntryForDoc(dom::Element* aElement) { + const nsRoleMapEntry* entry = aria::GetRoleMap(aElement); + if (!entry || entry->role == roles::APPLICATION || + entry->role == roles::DIALOG || + // Role alert isn't valid on the body element according to the ARIA spec, + // but it's useful for our UI; e.g. the WebRTC sharing indicator. + (entry->role == roles::ALERT && !mDocumentNode->IsContentDocument())) { + SetRoleMapEntry(entry); + return; + } + // No other ARIA roles are valid on body elements. + SetRoleMapEntry(nullptr); +} + +LocalAccessible* DocAccessible::GetAccessible(nsINode* aNode) const { + return aNode == mDocumentNode ? const_cast<DocAccessible*>(this) + : mNodeToAccessibleMap.Get(aNode); +} + +bool DocAccessible::HasPrimaryAction() const { + if (HyperTextAccessible::HasPrimaryAction()) { + return true; + } + // mContent is normally the body, but there might be a click listener on the + // root. + dom::Element* root = mDocumentNode->GetRootElement(); + if (mContent != root) { + return nsCoreUtils::HasClickListener(root); + } + return false; +} + +void DocAccessible::ActionNameAt(uint8_t aIndex, nsAString& aName) { + aName.Truncate(); + if (aIndex != 0) { + return; + } + if (HasPrimaryAction()) { + aName.AssignLiteral("click"); + } +} + +void DocAccessible::MaybeHandleChangeToHiddenNameOrDescription( + nsIContent* aChild) { + if (!HasLoadState(eTreeConstructed)) { + return; + } + for (nsIContent* content = aChild; content; content = content->GetParent()) { + if (HasAccessible(content)) { + // This node isn't hidden. Events for name/description dependents will be + // fired elsewhere. + break; + } + nsAtom* id = content->GetID(); + if (!id) { + continue; + } + auto* providers = + GetRelProviders(content->AsElement(), nsDependentAtomString(id)); + if (!providers) { + continue; + } + for (auto& provider : *providers) { + if (provider->mRelAttr != nsGkAtoms::aria_labelledby && + provider->mRelAttr != nsGkAtoms::aria_describedby) { + continue; + } + LocalAccessible* dependentAcc = GetAccessible(provider->mContent); + if (!dependentAcc) { + continue; + } + FireDelayedEvent(provider->mRelAttr == nsGkAtoms::aria_labelledby + ? nsIAccessibleEvent::EVENT_NAME_CHANGE + : nsIAccessibleEvent::EVENT_DESCRIPTION_CHANGE, + dependentAcc); + } + } +} |