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-rw-r--r--accessible/base/nsAccessibilityService.cpp1901
1 files changed, 1901 insertions, 0 deletions
diff --git a/accessible/base/nsAccessibilityService.cpp b/accessible/base/nsAccessibilityService.cpp
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+++ b/accessible/base/nsAccessibilityService.cpp
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 "nsAccessibilityService.h"
+
+// NOTE: alphabetically ordered
+#include "AccAttributes.h"
+#include "ApplicationAccessibleWrap.h"
+#include "ARIAGridAccessible.h"
+#include "ARIAMap.h"
+#include "DocAccessible-inl.h"
+#include "DocAccessibleChild.h"
+#include "FocusManager.h"
+#include "HTMLCanvasAccessible.h"
+#include "HTMLElementAccessibles.h"
+#include "HTMLImageMapAccessible.h"
+#include "HTMLLinkAccessible.h"
+#include "HTMLListAccessible.h"
+#include "HTMLSelectAccessible.h"
+#include "HTMLTableAccessible.h"
+#include "HyperTextAccessibleWrap.h"
+#include "RootAccessible.h"
+#include "StyleInfo.h"
+#include "nsAccUtils.h"
+#include "nsArrayUtils.h"
+#include "nsAttrName.h"
+#include "nsDOMTokenList.h"
+#include "nsCRT.h"
+#include "nsEventShell.h"
+#include "nsGkAtoms.h"
+#include "nsIFrameInlines.h"
+#include "nsServiceManagerUtils.h"
+#include "nsTextFormatter.h"
+#include "OuterDocAccessible.h"
+#include "Role.h"
+#ifdef MOZ_ACCESSIBILITY_ATK
+# include "RootAccessibleWrap.h"
+#endif
+#include "States.h"
+#include "Statistics.h"
+#include "TextLeafAccessible.h"
+#include "TreeWalker.h"
+#include "xpcAccessibleApplication.h"
+
+#ifdef XP_WIN
+# include "mozilla/a11y/Compatibility.h"
+# include "mozilla/StaticPtr.h"
+#endif
+
+#ifdef A11Y_LOG
+# include "Logging.h"
+#endif
+
+#include "nsExceptionHandler.h"
+#include "nsImageFrame.h"
+#include "nsINamed.h"
+#include "nsIObserverService.h"
+#include "nsMenuPopupFrame.h"
+#include "nsLayoutUtils.h"
+#include "nsTreeBodyFrame.h"
+#include "nsTreeColumns.h"
+#include "nsTreeUtils.h"
+#include "mozilla/a11y/AccTypes.h"
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/dom/DOMStringList.h"
+#include "mozilla/dom/EventTarget.h"
+#include "mozilla/dom/HTMLTableElement.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/ProfilerMarkers.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/Services.h"
+
+#include "XULAlertAccessible.h"
+#include "XULComboboxAccessible.h"
+#include "XULElementAccessibles.h"
+#include "XULFormControlAccessible.h"
+#include "XULListboxAccessible.h"
+#include "XULMenuAccessible.h"
+#include "XULTabAccessible.h"
+#include "XULTreeGridAccessible.h"
+
+using namespace mozilla;
+using namespace mozilla::a11y;
+using namespace mozilla::dom;
+
+/**
+ * Accessibility service force enable/disable preference.
+ * Supported values:
+ * Accessibility is force enabled (accessibility should always be enabled): -1
+ * Accessibility is enabled (will be started upon a request, default value): 0
+ * Accessibility is force disabled (never enable accessibility): 1
+ */
+#define PREF_ACCESSIBILITY_FORCE_DISABLED "accessibility.force_disabled"
+
+////////////////////////////////////////////////////////////////////////////////
+// Statics
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * If the element has an ARIA attribute that requires a specific Accessible
+ * class, create and return it. Otherwise, return null.
+ */
+static LocalAccessible* MaybeCreateSpecificARIAAccessible(
+ const nsRoleMapEntry* aRoleMapEntry, const LocalAccessible* aContext,
+ nsIContent* aContent, DocAccessible* aDocument) {
+ if (aRoleMapEntry && aRoleMapEntry->accTypes & eTableCell) {
+ if (aContent->IsAnyOfHTMLElements(nsGkAtoms::td, nsGkAtoms::th) &&
+ aContext->IsHTMLTableRow()) {
+ // Don't use ARIAGridCellAccessible for a valid td/th because
+ // HTMLTableCellAccessible can provide additional info; e.g. row/col span
+ // from the layout engine.
+ return nullptr;
+ }
+ // A cell must be in a row.
+ if (aContext->Role() != roles::ROW) {
+ return nullptr;
+ }
+ // That row must be in a table, though there may be an intervening rowgroup.
+ Accessible* parent = aContext->GetNonGenericParent();
+ if (!parent) {
+ return nullptr;
+ }
+ if (!parent->IsTable() && parent->Role() == roles::GROUPING) {
+ parent = parent->GetNonGenericParent();
+ if (!parent) {
+ return nullptr;
+ }
+ }
+ if (parent->IsTable()) {
+ return new ARIAGridCellAccessible(aContent, aDocument);
+ }
+ }
+ return nullptr;
+}
+
+/**
+ * Return true if the element has an attribute (ARIA, title, or relation) that
+ * requires the creation of an Accessible for the element.
+ */
+static bool AttributesMustBeAccessible(nsIContent* aContent,
+ DocAccessible* aDocument) {
+ if (aContent->IsElement()) {
+ uint32_t attrCount = aContent->AsElement()->GetAttrCount();
+ for (uint32_t attrIdx = 0; attrIdx < attrCount; attrIdx++) {
+ const nsAttrName* attr = aContent->AsElement()->GetAttrNameAt(attrIdx);
+ if (attr->NamespaceEquals(kNameSpaceID_None)) {
+ nsAtom* attrAtom = attr->Atom();
+ if (attrAtom == nsGkAtoms::title && aContent->IsHTMLElement()) {
+ // If the author provided a title on an element that would not
+ // be accessible normally, assume an intent and make it accessible.
+ return true;
+ }
+
+ nsDependentAtomString attrStr(attrAtom);
+ if (!StringBeginsWith(attrStr, u"aria-"_ns)) continue; // not ARIA
+
+ // A global state or a property and in case of token defined.
+ uint8_t attrFlags = aria::AttrCharacteristicsFor(attrAtom);
+ if ((attrFlags & ATTR_GLOBAL) &&
+ (!(attrFlags & ATTR_VALTOKEN) ||
+ nsAccUtils::HasDefinedARIAToken(aContent, attrAtom))) {
+ return true;
+ }
+ }
+ }
+
+ // If the given ID is referred by relation attribute then create an
+ // Accessible for it.
+ nsAutoString id;
+ if (nsCoreUtils::GetID(aContent, id) && !id.IsEmpty()) {
+ return aDocument->IsDependentID(aContent->AsElement(), id);
+ }
+ }
+
+ return false;
+}
+
+/**
+ * Return true if the element must be a generic Accessible, even if it has been
+ * marked presentational with role="presentation", etc. MustBeAccessible causes
+ * an Accessible to be created as if it weren't marked presentational at all;
+ * e.g. <table role="presentation" tabindex="0"> will expose roles::TABLE and
+ * support TableAccessible. In contrast, this function causes a generic
+ * Accessible to be created; e.g. <table role="presentation" style="position:
+ * fixed;"> will expose roles::TEXT_CONTAINER and will not support
+ * TableAccessible. This is necessary in certain cases for the
+ * RemoteAccessible cache.
+ */
+static bool MustBeGenericAccessible(nsIContent* aContent,
+ DocAccessible* aDocument) {
+ if (aContent->IsInNativeAnonymousSubtree() || aContent->IsSVGElement()) {
+ // We should not force create accs for anonymous content.
+ // This is an issue for inputs, which have an intermediate
+ // container with relevant overflow styling between the input
+ // and its internal input content.
+ // We should also avoid this for SVG elements (ie. `<foreignobject>`s
+ // which have default overflow:hidden styling).
+ return false;
+ }
+ nsIFrame* frame = aContent->GetPrimaryFrame();
+ MOZ_ASSERT(frame);
+ nsAutoCString overflow;
+ frame->Style()->GetComputedPropertyValue(eCSSProperty_overflow, overflow);
+ // If the frame has been transformed, and the content has any children, we
+ // should create an Accessible so that we can account for the transform when
+ // calculating the Accessible's bounds using the parent process cache.
+ // Ditto for content which is position: fixed or sticky or has overflow
+ // styling (auto, scroll, hidden).
+ // However, don't do this for XUL widgets, as this breaks XUL a11y code
+ // expectations in some cases. XUL widgets are only used in the parent
+ // process and can't be cached anyway.
+ return !aContent->IsXULElement() &&
+ ((aContent->HasChildren() && frame->IsTransformed()) ||
+ frame->IsStickyPositioned() ||
+ (frame->StyleDisplay()->mPosition == StylePositionProperty::Fixed &&
+ nsLayoutUtils::IsReallyFixedPos(frame)) ||
+ overflow.Equals("auto"_ns) || overflow.Equals("scroll"_ns) ||
+ overflow.Equals("hidden"_ns));
+}
+
+/**
+ * Return true if the element must be accessible.
+ */
+static bool MustBeAccessible(nsIContent* aContent, DocAccessible* aDocument) {
+ nsIFrame* frame = aContent->GetPrimaryFrame();
+ MOZ_ASSERT(frame);
+ // This document might be invisible when it first loads. Therefore, we must
+ // check focusability irrespective of visibility here. Otherwise, we might not
+ // create Accessibles for some focusable elements; e.g. a span with only a
+ // tabindex. Elements that are invisible within this document are excluded
+ // earlier in CreateAccessible.
+ if (frame->IsFocusable(/* aWithMouse */ false,
+ /* aCheckVisibility */ false)) {
+ return true;
+ }
+
+ return AttributesMustBeAccessible(aContent, aDocument);
+}
+
+bool nsAccessibilityService::ShouldCreateImgAccessible(
+ mozilla::dom::Element* aElement, DocAccessible* aDocument) {
+ // The element must have a layout frame for us to proceed. If there is no
+ // frame, the image is likely hidden.
+ nsIFrame* frame = aElement->GetPrimaryFrame();
+ if (!frame) {
+ return false;
+ }
+
+ // If the element is not an img, and also not an embedded image via embed or
+ // object, then we should not create an accessible.
+ if (!aElement->IsHTMLElement(nsGkAtoms::img) &&
+ ((!aElement->IsHTMLElement(nsGkAtoms::embed) &&
+ !aElement->IsHTMLElement(nsGkAtoms::object)) ||
+ frame->AccessibleType() != AccType::eImageType)) {
+ return false;
+ }
+
+ nsAutoString newAltText;
+ const bool hasAlt = aElement->GetAttr(nsGkAtoms::alt, newAltText);
+ if (!hasAlt || !newAltText.IsEmpty()) {
+ // If there is no alt attribute, we should create an accessible. The
+ // author may have missed the attribute, and the AT may want to provide a
+ // name. If there is alt text, we should create an accessible.
+ return true;
+ }
+
+ if (newAltText.IsEmpty() && (nsCoreUtils::HasClickListener(aElement) ||
+ MustBeAccessible(aElement, aDocument))) {
+ // If there is empty alt text, but there is a click listener for this img,
+ // or if it otherwise must be an accessible (e.g., if it has an aria-label
+ // attribute), we should create an accessible.
+ return true;
+ }
+
+ // Otherwise, no alt text means we should not create an accessible.
+ return false;
+}
+
+/**
+ * Return true if the SVG element should be accessible
+ */
+static bool MustSVGElementBeAccessible(nsIContent* aContent,
+ DocAccessible* aDocument) {
+ // https://w3c.github.io/svg-aam/#include_elements
+ for (nsIContent* childElm = aContent->GetFirstChild(); childElm;
+ childElm = childElm->GetNextSibling()) {
+ if (childElm->IsAnyOfSVGElements(nsGkAtoms::title, nsGkAtoms::desc)) {
+ return true;
+ }
+ }
+ return MustBeAccessible(aContent, aDocument);
+}
+
+/**
+ * Used by XULMap.h to map both menupopup and popup elements
+ */
+LocalAccessible* CreateMenupopupAccessible(Element* aElement,
+ LocalAccessible* aContext) {
+#ifdef MOZ_ACCESSIBILITY_ATK
+ // ATK considers this node to be redundant when within menubars, and it makes
+ // menu navigation with assistive technologies more difficult
+ // XXX In the future we will should this for consistency across the
+ // nsIAccessible implementations on each platform for a consistent scripting
+ // environment, but then strip out redundant accessibles in the AccessibleWrap
+ // class for each platform.
+ nsIContent* parent = aElement->GetParent();
+ if (parent && parent->IsXULElement(nsGkAtoms::menu)) return nullptr;
+#endif
+
+ return new XULMenupopupAccessible(aElement, aContext->Document());
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// LocalAccessible constructors
+
+static LocalAccessible* New_HyperText(Element* aElement,
+ LocalAccessible* aContext) {
+ return new HyperTextAccessibleWrap(aElement, aContext->Document());
+}
+
+template <typename AccClass>
+static LocalAccessible* New_HTMLDtOrDd(Element* aElement,
+ LocalAccessible* aContext) {
+ nsIContent* parent = aContext->GetContent();
+ if (parent->IsHTMLElement(nsGkAtoms::div)) {
+ // It is conforming in HTML to use a div to group dt/dd elements.
+ parent = parent->GetParent();
+ }
+
+ if (parent && parent->IsHTMLElement(nsGkAtoms::dl)) {
+ return new AccClass(aElement, aContext->Document());
+ }
+
+ return nullptr;
+}
+
+/**
+ * Cached value of the PREF_ACCESSIBILITY_FORCE_DISABLED preference.
+ */
+static int32_t sPlatformDisabledState = 0;
+
+////////////////////////////////////////////////////////////////////////////////
+// Markup maps array.
+
+#define Attr(name, value) \
+ { nsGkAtoms::name, nsGkAtoms::value }
+
+#define AttrFromDOM(name, DOMAttrName) \
+ { nsGkAtoms::name, nullptr, nsGkAtoms::DOMAttrName }
+
+#define AttrFromDOMIf(name, DOMAttrName, DOMAttrValue) \
+ { nsGkAtoms::name, nullptr, nsGkAtoms::DOMAttrName, nsGkAtoms::DOMAttrValue }
+
+#define MARKUPMAP(atom, new_func, r, ...) \
+ {nsGkAtoms::atom, new_func, static_cast<a11y::role>(r), {__VA_ARGS__}},
+
+static const MarkupMapInfo sHTMLMarkupMapList[] = {
+#include "HTMLMarkupMap.h"
+};
+
+static const MarkupMapInfo sMathMLMarkupMapList[] = {
+#include "MathMLMarkupMap.h"
+};
+
+#undef MARKUPMAP
+
+#define XULMAP(atom, ...) {nsGkAtoms::atom, __VA_ARGS__},
+
+#define XULMAP_TYPE(atom, new_type) \
+ XULMAP( \
+ atom, \
+ [](Element* aElement, LocalAccessible* aContext) -> LocalAccessible* { \
+ return new new_type(aElement, aContext->Document()); \
+ })
+
+static const XULMarkupMapInfo sXULMarkupMapList[] = {
+#include "XULMap.h"
+};
+
+#undef XULMAP_TYPE
+#undef XULMAP
+
+#undef Attr
+#undef AttrFromDOM
+#undef AttrFromDOMIf
+
+////////////////////////////////////////////////////////////////////////////////
+// nsAccessibilityService
+////////////////////////////////////////////////////////////////////////////////
+
+nsAccessibilityService* nsAccessibilityService::gAccessibilityService = nullptr;
+ApplicationAccessible* nsAccessibilityService::gApplicationAccessible = nullptr;
+xpcAccessibleApplication* nsAccessibilityService::gXPCApplicationAccessible =
+ nullptr;
+uint32_t nsAccessibilityService::gConsumers = 0;
+
+nsAccessibilityService::nsAccessibilityService()
+ : DocManager(),
+ FocusManager(),
+ mHTMLMarkupMap(ArrayLength(sHTMLMarkupMapList)),
+ mMathMLMarkupMap(ArrayLength(sMathMLMarkupMapList)),
+ mXULMarkupMap(ArrayLength(sXULMarkupMapList)) {}
+
+nsAccessibilityService::~nsAccessibilityService() {
+ NS_ASSERTION(IsShutdown(), "Accessibility wasn't shutdown!");
+ gAccessibilityService = nullptr;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsIListenerChangeListener
+
+NS_IMETHODIMP
+nsAccessibilityService::ListenersChanged(nsIArray* aEventChanges) {
+ uint32_t targetCount;
+ nsresult rv = aEventChanges->GetLength(&targetCount);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ for (uint32_t i = 0; i < targetCount; i++) {
+ nsCOMPtr<nsIEventListenerChange> change =
+ do_QueryElementAt(aEventChanges, i);
+
+ RefPtr<EventTarget> target;
+ change->GetTarget(getter_AddRefs(target));
+ nsIContent* content(nsIContent::FromEventTargetOrNull(target));
+ if (!content || !content->IsHTMLElement()) {
+ continue;
+ }
+
+ uint32_t changeCount;
+ change->GetCountOfEventListenerChangesAffectingAccessibility(&changeCount);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ if (changeCount) {
+ Document* ownerDoc = content->OwnerDoc();
+ DocAccessible* document = GetExistingDocAccessible(ownerDoc);
+
+ if (document) {
+ LocalAccessible* acc = document->GetAccessible(content);
+ if (!acc && (content == document->GetContent() ||
+ content == document->DocumentNode()->GetRootElement())) {
+ acc = document;
+ }
+ if (!acc && nsCoreUtils::HasClickListener(content)) {
+ // Create an accessible for a inaccessible element having click event
+ // handler.
+ document->ContentInserted(content, content->GetNextSibling());
+ } else if (acc) {
+ if (acc->IsHTMLLink() && !acc->AsHTMLLink()->IsLinked()) {
+ // Notify of a LINKED state change if an HTML link gets a click
+ // listener but does not have an href attribute.
+ RefPtr<AccEvent> linkedChangeEvent =
+ new AccStateChangeEvent(acc, states::LINKED);
+ document->FireDelayedEvent(linkedChangeEvent);
+ }
+
+ // A click listener change might mean losing or gaining an action.
+ acc->SendCache(CacheDomain::Actions, CacheUpdateType::Update);
+ }
+ }
+ }
+ }
+ return NS_OK;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsISupports
+
+NS_IMPL_ISUPPORTS_INHERITED(nsAccessibilityService, DocManager, nsIObserver,
+ nsIListenerChangeListener,
+ nsISelectionListener) // from SelectionManager
+
+////////////////////////////////////////////////////////////////////////////////
+// nsIObserver
+
+NS_IMETHODIMP
+nsAccessibilityService::Observe(nsISupports* aSubject, const char* aTopic,
+ const char16_t* aData) {
+ if (!nsCRT::strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID)) {
+ Shutdown();
+ }
+
+ return NS_OK;
+}
+
+void nsAccessibilityService::NotifyOfAnchorJumpTo(nsIContent* aTargetNode) {
+ Document* documentNode = aTargetNode->GetUncomposedDoc();
+ if (documentNode) {
+ DocAccessible* document = GetDocAccessible(documentNode);
+ if (document) document->SetAnchorJump(aTargetNode);
+ }
+}
+
+void nsAccessibilityService::FireAccessibleEvent(uint32_t aEvent,
+ LocalAccessible* aTarget) {
+ nsEventShell::FireEvent(aEvent, aTarget);
+}
+
+void nsAccessibilityService::NotifyOfPossibleBoundsChange(
+ mozilla::PresShell* aPresShell, nsIContent* aContent) {
+ if (IPCAccessibilityActive()) {
+ DocAccessible* document = aPresShell->GetDocAccessible();
+ if (document) {
+ // DocAccessible::GetAccessible() won't return the document if a root
+ // element like body is passed.
+ LocalAccessible* accessible = aContent == document->GetContent()
+ ? document
+ : document->GetAccessible(aContent);
+ if (accessible) {
+ document->QueueCacheUpdate(accessible, CacheDomain::Bounds);
+ }
+ }
+ }
+}
+
+void nsAccessibilityService::NotifyOfComputedStyleChange(
+ mozilla::PresShell* aPresShell, nsIContent* aContent) {
+ DocAccessible* document = aPresShell->GetDocAccessible();
+ if (!document) {
+ return;
+ }
+
+ // DocAccessible::GetAccessible() won't return the document if a root
+ // element like body is passed.
+ LocalAccessible* accessible = aContent == document->GetContent()
+ ? document
+ : document->GetAccessible(aContent);
+ if (!accessible && aContent && aContent->HasChildren() &&
+ !aContent->IsInNativeAnonymousSubtree()) {
+ // If the content has children and its frame has a transform, create an
+ // Accessible so that we can account for the transform when calculating
+ // the Accessible's bounds using the parent process cache. Ditto for
+ // position: fixed/sticky and content with overflow styling (hidden, auto,
+ // scroll)
+ if (const nsIFrame* frame = aContent->GetPrimaryFrame()) {
+ const auto& disp = *frame->StyleDisplay();
+ if (disp.HasTransform(frame) ||
+ disp.mPosition == StylePositionProperty::Fixed ||
+ disp.mPosition == StylePositionProperty::Sticky ||
+ disp.IsScrollableOverflow()) {
+ document->ContentInserted(aContent, aContent->GetNextSibling());
+ }
+ }
+ } else if (accessible && IPCAccessibilityActive()) {
+ accessible->MaybeQueueCacheUpdateForStyleChanges();
+ }
+}
+
+void nsAccessibilityService::NotifyOfResolutionChange(
+ mozilla::PresShell* aPresShell, float aResolution) {
+ DocAccessible* document = aPresShell->GetDocAccessible();
+ if (document && document->IPCDoc()) {
+ AutoTArray<mozilla::a11y::CacheData, 1> data;
+ RefPtr<AccAttributes> fields = new AccAttributes();
+ fields->SetAttribute(nsGkAtoms::resolution, aResolution);
+ data.AppendElement(mozilla::a11y::CacheData(0, fields));
+ document->IPCDoc()->SendCache(CacheUpdateType::Update, data);
+ }
+}
+
+void nsAccessibilityService::NotifyOfDevPixelRatioChange(
+ mozilla::PresShell* aPresShell, int32_t aAppUnitsPerDevPixel) {
+ DocAccessible* document = aPresShell->GetDocAccessible();
+ if (document && document->IPCDoc()) {
+ AutoTArray<mozilla::a11y::CacheData, 1> data;
+ RefPtr<AccAttributes> fields = new AccAttributes();
+ fields->SetAttribute(nsGkAtoms::_moz_device_pixel_ratio,
+ aAppUnitsPerDevPixel);
+ data.AppendElement(mozilla::a11y::CacheData(0, fields));
+ document->IPCDoc()->SendCache(CacheUpdateType::Update, data);
+ }
+}
+
+LocalAccessible* nsAccessibilityService::GetRootDocumentAccessible(
+ PresShell* aPresShell, bool aCanCreate) {
+ PresShell* presShell = aPresShell;
+ Document* documentNode = aPresShell->GetDocument();
+ if (documentNode) {
+ nsCOMPtr<nsIDocShellTreeItem> treeItem(documentNode->GetDocShell());
+ if (treeItem) {
+ nsCOMPtr<nsIDocShellTreeItem> rootTreeItem;
+ treeItem->GetInProcessRootTreeItem(getter_AddRefs(rootTreeItem));
+ if (treeItem != rootTreeItem) {
+ nsCOMPtr<nsIDocShell> docShell(do_QueryInterface(rootTreeItem));
+ presShell = docShell->GetPresShell();
+ }
+
+ return aCanCreate ? GetDocAccessible(presShell)
+ : presShell->GetDocAccessible();
+ }
+ }
+ return nullptr;
+}
+
+void nsAccessibilityService::NotifyOfTabPanelVisibilityChange(
+ PresShell* aPresShell, Element* aPanel, bool aNowVisible) {
+ MOZ_ASSERT(aPanel->GetParent()->IsXULElement(nsGkAtoms::tabpanels));
+
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (!document) {
+ return;
+ }
+
+ if (LocalAccessible* acc = document->GetAccessible(aPanel)) {
+ RefPtr<AccEvent> event =
+ new AccStateChangeEvent(acc, states::OFFSCREEN, aNowVisible);
+ document->FireDelayedEvent(event);
+ }
+}
+
+void nsAccessibilityService::ContentRangeInserted(PresShell* aPresShell,
+ nsIContent* aStartChild,
+ nsIContent* aEndChild) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+#ifdef A11Y_LOG
+ if (logging::IsEnabled(logging::eTree)) {
+ logging::MsgBegin("TREE", "content inserted; doc: %p", document);
+ logging::Node("container", aStartChild->GetParentNode());
+ for (nsIContent* child = aStartChild; child != aEndChild;
+ child = child->GetNextSibling()) {
+ logging::Node("content", child);
+ }
+ logging::MsgEnd();
+ logging::Stack();
+ }
+#endif
+
+ if (document) {
+ document->ContentInserted(aStartChild, aEndChild);
+ }
+}
+
+void nsAccessibilityService::ScheduleAccessibilitySubtreeUpdate(
+ PresShell* aPresShell, nsIContent* aContent) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+#ifdef A11Y_LOG
+ if (logging::IsEnabled(logging::eTree)) {
+ logging::MsgBegin("TREE", "schedule update; doc: %p", document);
+ logging::Node("content node", aContent);
+ logging::MsgEnd();
+ }
+#endif
+
+ if (document) {
+ document->ScheduleTreeUpdate(aContent);
+ }
+}
+
+void nsAccessibilityService::ContentRemoved(PresShell* aPresShell,
+ nsIContent* aChildNode) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+#ifdef A11Y_LOG
+ if (logging::IsEnabled(logging::eTree)) {
+ logging::MsgBegin("TREE", "content removed; doc: %p", document);
+ logging::Node("container node", aChildNode->GetFlattenedTreeParent());
+ logging::Node("content node", aChildNode);
+ logging::MsgEnd();
+ }
+#endif
+
+ if (document) {
+ document->ContentRemoved(aChildNode);
+ }
+
+#ifdef A11Y_LOG
+ if (logging::IsEnabled(logging::eTree)) {
+ logging::MsgEnd();
+ logging::Stack();
+ }
+#endif
+}
+
+void nsAccessibilityService::TableLayoutGuessMaybeChanged(
+ PresShell* aPresShell, nsIContent* aContent) {
+ if (DocAccessible* document = GetDocAccessible(aPresShell)) {
+ if (LocalAccessible* acc = document->GetAccessible(aContent)) {
+ if (LocalAccessible* table = nsAccUtils::TableFor(acc)) {
+ document->QueueCacheUpdate(table, CacheDomain::Table);
+ }
+ }
+ }
+}
+
+void nsAccessibilityService::ComboboxOptionMaybeChanged(
+ PresShell* aPresShell, nsIContent* aMutatingNode) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (!document) {
+ return;
+ }
+
+ for (nsIContent* cur = aMutatingNode; cur; cur = cur->GetParent()) {
+ if (cur->IsHTMLElement(nsGkAtoms::option)) {
+ if (LocalAccessible* accessible = document->GetAccessible(cur)) {
+ document->FireDelayedEvent(nsIAccessibleEvent::EVENT_NAME_CHANGE,
+ accessible);
+ break;
+ }
+ if (cur->IsHTMLElement(nsGkAtoms::select)) {
+ break;
+ }
+ }
+ }
+}
+
+void nsAccessibilityService::UpdateText(PresShell* aPresShell,
+ nsIContent* aContent) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (document) document->UpdateText(aContent);
+}
+
+void nsAccessibilityService::TreeViewChanged(PresShell* aPresShell,
+ nsIContent* aContent,
+ nsITreeView* aView) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (document) {
+ LocalAccessible* accessible = document->GetAccessible(aContent);
+ if (accessible) {
+ XULTreeAccessible* treeAcc = accessible->AsXULTree();
+ if (treeAcc) treeAcc->TreeViewChanged(aView);
+ }
+ }
+}
+
+void nsAccessibilityService::RangeValueChanged(PresShell* aPresShell,
+ nsIContent* aContent) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (document) {
+ LocalAccessible* accessible = document->GetAccessible(aContent);
+ if (accessible) {
+ document->FireDelayedEvent(nsIAccessibleEvent::EVENT_VALUE_CHANGE,
+ accessible);
+ }
+ }
+}
+
+void nsAccessibilityService::UpdateImageMap(nsImageFrame* aImageFrame) {
+ PresShell* presShell = aImageFrame->PresShell();
+ DocAccessible* document = GetDocAccessible(presShell);
+ if (document) {
+ LocalAccessible* accessible =
+ document->GetAccessible(aImageFrame->GetContent());
+ if (accessible) {
+ HTMLImageMapAccessible* imageMap = accessible->AsImageMap();
+ if (imageMap) {
+ imageMap->UpdateChildAreas();
+ return;
+ }
+
+ // If image map was initialized after we created an accessible (that'll
+ // be an image accessible) then recreate it.
+ RecreateAccessible(presShell, aImageFrame->GetContent());
+ }
+ }
+}
+
+void nsAccessibilityService::UpdateLabelValue(PresShell* aPresShell,
+ nsIContent* aLabelElm,
+ const nsString& aNewValue) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (document) {
+ LocalAccessible* accessible = document->GetAccessible(aLabelElm);
+ if (accessible) {
+ XULLabelAccessible* xulLabel = accessible->AsXULLabel();
+ NS_ASSERTION(xulLabel,
+ "UpdateLabelValue was called for wrong accessible!");
+ if (xulLabel) xulLabel->UpdateLabelValue(aNewValue);
+ }
+ }
+}
+
+void nsAccessibilityService::PresShellActivated(PresShell* aPresShell) {
+ DocAccessible* document = aPresShell->GetDocAccessible();
+ if (document) {
+ RootAccessible* rootDocument = document->RootAccessible();
+ NS_ASSERTION(rootDocument, "Entirely broken tree: no root document!");
+ if (rootDocument) rootDocument->DocumentActivated(document);
+ }
+}
+
+void nsAccessibilityService::RecreateAccessible(PresShell* aPresShell,
+ nsIContent* aContent) {
+ DocAccessible* document = GetDocAccessible(aPresShell);
+ if (document) document->RecreateAccessible(aContent);
+}
+
+void nsAccessibilityService::GetStringRole(uint32_t aRole, nsAString& aString) {
+#define ROLE(geckoRole, stringRole, ariaRole, atkRole, macRole, macSubrole, \
+ msaaRole, ia2Role, androidClass, nameRule) \
+ case roles::geckoRole: \
+ aString.AssignLiteral(stringRole); \
+ return;
+
+ switch (aRole) {
+#include "RoleMap.h"
+ default:
+ aString.AssignLiteral("unknown");
+ return;
+ }
+
+#undef ROLE
+}
+
+void nsAccessibilityService::GetStringStates(uint32_t aState,
+ uint32_t aExtraState,
+ nsISupports** aStringStates) {
+ RefPtr<DOMStringList> stringStates =
+ GetStringStates(nsAccUtils::To64State(aState, aExtraState));
+
+ // unknown state
+ if (!stringStates->Length()) {
+ stringStates->Add(u"unknown"_ns);
+ }
+
+ stringStates.forget(aStringStates);
+}
+
+already_AddRefed<DOMStringList> nsAccessibilityService::GetStringStates(
+ uint64_t aStates) const {
+ RefPtr<DOMStringList> stringStates = new DOMStringList();
+
+ if (aStates & states::UNAVAILABLE) {
+ stringStates->Add(u"unavailable"_ns);
+ }
+ if (aStates & states::SELECTED) {
+ stringStates->Add(u"selected"_ns);
+ }
+ if (aStates & states::FOCUSED) {
+ stringStates->Add(u"focused"_ns);
+ }
+ if (aStates & states::PRESSED) {
+ stringStates->Add(u"pressed"_ns);
+ }
+ if (aStates & states::CHECKED) {
+ stringStates->Add(u"checked"_ns);
+ }
+ if (aStates & states::MIXED) {
+ stringStates->Add(u"mixed"_ns);
+ }
+ if (aStates & states::READONLY) {
+ stringStates->Add(u"readonly"_ns);
+ }
+ if (aStates & states::HOTTRACKED) {
+ stringStates->Add(u"hottracked"_ns);
+ }
+ if (aStates & states::DEFAULT) {
+ stringStates->Add(u"default"_ns);
+ }
+ if (aStates & states::EXPANDED) {
+ stringStates->Add(u"expanded"_ns);
+ }
+ if (aStates & states::COLLAPSED) {
+ stringStates->Add(u"collapsed"_ns);
+ }
+ if (aStates & states::BUSY) {
+ stringStates->Add(u"busy"_ns);
+ }
+ if (aStates & states::FLOATING) {
+ stringStates->Add(u"floating"_ns);
+ }
+ if (aStates & states::ANIMATED) {
+ stringStates->Add(u"animated"_ns);
+ }
+ if (aStates & states::INVISIBLE) {
+ stringStates->Add(u"invisible"_ns);
+ }
+ if (aStates & states::OFFSCREEN) {
+ stringStates->Add(u"offscreen"_ns);
+ }
+ if (aStates & states::SIZEABLE) {
+ stringStates->Add(u"sizeable"_ns);
+ }
+ if (aStates & states::MOVEABLE) {
+ stringStates->Add(u"moveable"_ns);
+ }
+ if (aStates & states::SELFVOICING) {
+ stringStates->Add(u"selfvoicing"_ns);
+ }
+ if (aStates & states::FOCUSABLE) {
+ stringStates->Add(u"focusable"_ns);
+ }
+ if (aStates & states::SELECTABLE) {
+ stringStates->Add(u"selectable"_ns);
+ }
+ if (aStates & states::LINKED) {
+ stringStates->Add(u"linked"_ns);
+ }
+ if (aStates & states::TRAVERSED) {
+ stringStates->Add(u"traversed"_ns);
+ }
+ if (aStates & states::MULTISELECTABLE) {
+ stringStates->Add(u"multiselectable"_ns);
+ }
+ if (aStates & states::EXTSELECTABLE) {
+ stringStates->Add(u"extselectable"_ns);
+ }
+ if (aStates & states::PROTECTED) {
+ stringStates->Add(u"protected"_ns);
+ }
+ if (aStates & states::HASPOPUP) {
+ stringStates->Add(u"haspopup"_ns);
+ }
+ if (aStates & states::REQUIRED) {
+ stringStates->Add(u"required"_ns);
+ }
+ if (aStates & states::ALERT) {
+ stringStates->Add(u"alert"_ns);
+ }
+ if (aStates & states::INVALID) {
+ stringStates->Add(u"invalid"_ns);
+ }
+ if (aStates & states::CHECKABLE) {
+ stringStates->Add(u"checkable"_ns);
+ }
+ if (aStates & states::SUPPORTS_AUTOCOMPLETION) {
+ stringStates->Add(u"autocompletion"_ns);
+ }
+ if (aStates & states::DEFUNCT) {
+ stringStates->Add(u"defunct"_ns);
+ }
+ if (aStates & states::SELECTABLE_TEXT) {
+ stringStates->Add(u"selectable text"_ns);
+ }
+ if (aStates & states::EDITABLE) {
+ stringStates->Add(u"editable"_ns);
+ }
+ if (aStates & states::ACTIVE) {
+ stringStates->Add(u"active"_ns);
+ }
+ if (aStates & states::MODAL) {
+ stringStates->Add(u"modal"_ns);
+ }
+ if (aStates & states::MULTI_LINE) {
+ stringStates->Add(u"multi line"_ns);
+ }
+ if (aStates & states::HORIZONTAL) {
+ stringStates->Add(u"horizontal"_ns);
+ }
+ if (aStates & states::OPAQUE1) {
+ stringStates->Add(u"opaque"_ns);
+ }
+ if (aStates & states::SINGLE_LINE) {
+ stringStates->Add(u"single line"_ns);
+ }
+ if (aStates & states::TRANSIENT) {
+ stringStates->Add(u"transient"_ns);
+ }
+ if (aStates & states::VERTICAL) {
+ stringStates->Add(u"vertical"_ns);
+ }
+ if (aStates & states::STALE) {
+ stringStates->Add(u"stale"_ns);
+ }
+ if (aStates & states::ENABLED) {
+ stringStates->Add(u"enabled"_ns);
+ }
+ if (aStates & states::SENSITIVE) {
+ stringStates->Add(u"sensitive"_ns);
+ }
+ if (aStates & states::EXPANDABLE) {
+ stringStates->Add(u"expandable"_ns);
+ }
+ if (aStates & states::PINNED) {
+ stringStates->Add(u"pinned"_ns);
+ }
+ if (aStates & states::CURRENT) {
+ stringStates->Add(u"current"_ns);
+ }
+
+ return stringStates.forget();
+}
+
+void nsAccessibilityService::GetStringEventType(uint32_t aEventType,
+ nsAString& aString) {
+ NS_ASSERTION(
+ nsIAccessibleEvent::EVENT_LAST_ENTRY == ArrayLength(kEventTypeNames),
+ "nsIAccessibleEvent constants are out of sync to kEventTypeNames");
+
+ if (aEventType >= ArrayLength(kEventTypeNames)) {
+ aString.AssignLiteral("unknown");
+ return;
+ }
+
+ aString.AssignASCII(kEventTypeNames[aEventType]);
+}
+
+void nsAccessibilityService::GetStringEventType(uint32_t aEventType,
+ nsACString& aString) {
+ MOZ_ASSERT(
+ nsIAccessibleEvent::EVENT_LAST_ENTRY == ArrayLength(kEventTypeNames),
+ "nsIAccessibleEvent constants are out of sync to kEventTypeNames");
+
+ if (aEventType >= ArrayLength(kEventTypeNames)) {
+ aString.AssignLiteral("unknown");
+ return;
+ }
+
+ aString = nsDependentCString(kEventTypeNames[aEventType]);
+}
+
+void nsAccessibilityService::GetStringRelationType(uint32_t aRelationType,
+ nsAString& aString) {
+ NS_ENSURE_TRUE_VOID(aRelationType <=
+ static_cast<uint32_t>(RelationType::LAST));
+
+#define RELATIONTYPE(geckoType, geckoTypeName, atkType, msaaType, ia2Type) \
+ case RelationType::geckoType: \
+ aString.AssignLiteral(geckoTypeName); \
+ return;
+
+ RelationType relationType = static_cast<RelationType>(aRelationType);
+ switch (relationType) {
+#include "RelationTypeMap.h"
+ default:
+ aString.AssignLiteral("unknown");
+ return;
+ }
+
+#undef RELATIONTYPE
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsAccessibilityService public
+
+LocalAccessible* nsAccessibilityService::CreateAccessible(
+ nsINode* aNode, LocalAccessible* aContext, bool* aIsSubtreeHidden) {
+ MOZ_ASSERT(aContext, "No context provided");
+ MOZ_ASSERT(aNode, "No node to create an accessible for");
+ MOZ_ASSERT(gConsumers, "No creation after shutdown");
+
+ if (aIsSubtreeHidden) *aIsSubtreeHidden = false;
+
+ DocAccessible* document = aContext->Document();
+ MOZ_ASSERT(!document->GetAccessible(aNode),
+ "We already have an accessible for this node.");
+
+ if (aNode->IsDocument()) {
+ // If it's document node then ask accessible document loader for
+ // document accessible, otherwise return null.
+ return GetDocAccessible(aNode->AsDocument());
+ }
+
+ // We have a content node.
+ if (!aNode->GetComposedDoc()) {
+ NS_WARNING("Creating accessible for node with no document");
+ return nullptr;
+ }
+
+ if (aNode->OwnerDoc() != document->DocumentNode()) {
+ NS_ERROR("Creating accessible for wrong document");
+ return nullptr;
+ }
+
+ if (!aNode->IsContent()) return nullptr;
+
+ nsIContent* content = aNode->AsContent();
+ if (aria::HasDefinedARIAHidden(content)) {
+ if (aIsSubtreeHidden) {
+ *aIsSubtreeHidden = true;
+ }
+ return nullptr;
+ }
+
+ // Check frame and its visibility.
+ nsIFrame* frame = content->GetPrimaryFrame();
+ if (frame) {
+ // If invisible or inert, we don't create an accessible, but we don't mark
+ // it with aIsSubtreeHidden = true, since visibility: hidden frame allows
+ // visible elements in subtree, and inert elements allow non-inert
+ // elements.
+ if (!frame->StyleVisibility()->IsVisible() || frame->StyleUI()->IsInert()) {
+ return nullptr;
+ }
+ } else if (nsCoreUtils::CanCreateAccessibleWithoutFrame(content)) {
+ // display:contents element doesn't have a frame, but retains the
+ // semantics. All its children are unaffected.
+ const nsRoleMapEntry* roleMapEntry = aria::GetRoleMap(content->AsElement());
+ RefPtr<LocalAccessible> newAcc = MaybeCreateSpecificARIAAccessible(
+ roleMapEntry, aContext, content, document);
+ const MarkupMapInfo* markupMap = nullptr;
+ if (!newAcc) {
+ markupMap = GetMarkupMapInfoFor(content);
+ if (markupMap && markupMap->new_func) {
+ newAcc = markupMap->new_func(content->AsElement(), aContext);
+ }
+ }
+
+ // Check whether this element has an ARIA role or attribute that requires
+ // us to create an Accessible.
+ const bool hasNonPresentationalARIARole =
+ roleMapEntry && !roleMapEntry->Is(nsGkAtoms::presentation) &&
+ !roleMapEntry->Is(nsGkAtoms::none);
+ if (!newAcc && (hasNonPresentationalARIARole ||
+ AttributesMustBeAccessible(content, document))) {
+ newAcc = new HyperTextAccessibleWrap(content, document);
+ }
+
+ // If there's still no Accessible but we do have an entry in the markup
+ // map for this non-presentational element, create a generic
+ // HyperTextAccessible.
+ if (!newAcc && markupMap &&
+ (!roleMapEntry || hasNonPresentationalARIARole)) {
+ newAcc = new HyperTextAccessibleWrap(content, document);
+ }
+
+ if (newAcc) {
+ document->BindToDocument(newAcc, roleMapEntry);
+ }
+ return newAcc;
+ } else {
+ if (aIsSubtreeHidden) {
+ *aIsSubtreeHidden = true;
+ }
+ return nullptr;
+ }
+
+ if (frame->IsHiddenByContentVisibilityOnAnyAncestor(
+ nsIFrame::IncludeContentVisibility::Hidden)) {
+ if (aIsSubtreeHidden) {
+ *aIsSubtreeHidden = true;
+ }
+ return nullptr;
+ }
+
+ if (nsMenuPopupFrame* popupFrame = do_QueryFrame(frame)) {
+ // Hidden tooltips and panels don't create accessibles in the whole subtree.
+ // Showing them gets handled by RootAccessible::ProcessDOMEvent.
+ if (content->IsAnyOfXULElements(nsGkAtoms::tooltip, nsGkAtoms::panel)) {
+ nsPopupState popupState = popupFrame->PopupState();
+ if (popupState == ePopupHiding || popupState == ePopupInvisible ||
+ popupState == ePopupClosed) {
+ if (aIsSubtreeHidden) {
+ *aIsSubtreeHidden = true;
+ }
+ return nullptr;
+ }
+ }
+ }
+
+ if (frame->GetContent() != content) {
+ // Not the main content for this frame. This happens because <area>
+ // elements return the image frame as their primary frame. The main content
+ // for the image frame is the image content. If the frame is not an image
+ // frame or the node is not an area element then null is returned.
+ // This setup will change when bug 135040 is fixed. Make sure we don't
+ // create area accessible here. Hopefully assertion below will handle that.
+
+#ifdef DEBUG
+ nsImageFrame* imageFrame = do_QueryFrame(frame);
+ NS_ASSERTION(imageFrame && content->IsHTMLElement(nsGkAtoms::area),
+ "Unknown case of not main content for the frame!");
+#endif
+ return nullptr;
+ }
+
+#ifdef DEBUG
+ nsImageFrame* imageFrame = do_QueryFrame(frame);
+ NS_ASSERTION(!imageFrame || !content->IsHTMLElement(nsGkAtoms::area),
+ "Image map manages the area accessible creation!");
+#endif
+
+ // Attempt to create an accessible based on what we know.
+ RefPtr<LocalAccessible> newAcc;
+
+ // Create accessible for visible text frames.
+ if (content->IsText()) {
+ nsIFrame::RenderedText text = frame->GetRenderedText(
+ 0, UINT32_MAX, nsIFrame::TextOffsetType::OffsetsInContentText,
+ nsIFrame::TrailingWhitespace::DontTrim);
+ // Ignore not rendered text nodes and whitespace text nodes between table
+ // cells.
+ if (text.mString.IsEmpty() ||
+ (aContext->IsTableRow() &&
+ nsCoreUtils::IsWhitespaceString(text.mString))) {
+ if (aIsSubtreeHidden) *aIsSubtreeHidden = true;
+
+ return nullptr;
+ }
+
+ newAcc = CreateAccessibleByFrameType(frame, content, aContext);
+ MOZ_ASSERT(newAcc, "Accessible not created for text node!");
+ document->BindToDocument(newAcc, nullptr);
+ newAcc->AsTextLeaf()->SetText(text.mString);
+ return newAcc;
+ }
+
+ if (content->IsHTMLElement(nsGkAtoms::map)) {
+ // Create hyper text accessible for HTML map if it is used to group links
+ // (see http://www.w3.org/TR/WCAG10-HTML-TECHS/#group-bypass). If the HTML
+ // map rect is empty then it is used for links grouping. Otherwise it should
+ // be used in conjunction with HTML image element and in this case we don't
+ // create any accessible for it and don't walk into it. The accessibles for
+ // HTML area (HTMLAreaAccessible) the map contains are attached as
+ // children of the appropriate accessible for HTML image
+ // (ImageAccessible).
+ if (nsLayoutUtils::GetAllInFlowRectsUnion(frame, frame->GetParent())
+ .IsEmpty()) {
+ if (aIsSubtreeHidden) *aIsSubtreeHidden = true;
+
+ return nullptr;
+ }
+
+ newAcc = new HyperTextAccessibleWrap(content, document);
+ document->BindToDocument(newAcc, aria::GetRoleMap(content->AsElement()));
+ return newAcc;
+ }
+
+ const nsRoleMapEntry* roleMapEntry = aria::GetRoleMap(content->AsElement());
+
+ if (roleMapEntry && (roleMapEntry->Is(nsGkAtoms::presentation) ||
+ roleMapEntry->Is(nsGkAtoms::none))) {
+ if (MustBeAccessible(content, document)) {
+ // If the element is focusable, a global ARIA attribute is applied to it
+ // or it is referenced by an ARIA relationship, then treat
+ // role="presentation" on the element as if the role is not there.
+ roleMapEntry = nullptr;
+ } else if (MustBeGenericAccessible(content, document)) {
+ // Clear roleMapEntry so that we use the generic role specified below.
+ // Otherwise, we'd expose roles::NOTHING as specified for presentation in
+ // ARIAMap.
+ roleMapEntry = nullptr;
+ newAcc = new EnumRoleHyperTextAccessible<roles::TEXT_CONTAINER>(content,
+ document);
+ } else {
+ return nullptr;
+ }
+ }
+
+ if (!newAcc && content->IsHTMLElement()) { // HTML accessibles
+ // We should always use OuterDocAccessible for OuterDocs, even if there's a
+ // specific ARIA class we would otherwise use.
+ if (frame->AccessibleType() != eOuterDocType) {
+ newAcc = MaybeCreateSpecificARIAAccessible(roleMapEntry, aContext,
+ content, document);
+ }
+
+ if (!newAcc) {
+ // Prefer to use markup to decide if and what kind of accessible to
+ // create,
+ const MarkupMapInfo* markupMap =
+ mHTMLMarkupMap.Get(content->NodeInfo()->NameAtom());
+ if (markupMap && markupMap->new_func) {
+ newAcc = markupMap->new_func(content->AsElement(), aContext);
+ }
+
+ if (!newAcc) { // try by frame accessible type.
+ newAcc = CreateAccessibleByFrameType(frame, content, aContext);
+ }
+ }
+
+ // If table has strong ARIA role then all table descendants shouldn't
+ // expose their native roles.
+ if (!roleMapEntry && newAcc && aContext->HasStrongARIARole()) {
+ if (frame->AccessibleType() == eHTMLTableRowType) {
+ const nsRoleMapEntry* contextRoleMap = aContext->ARIARoleMap();
+ if (!contextRoleMap->IsOfType(eTable)) {
+ roleMapEntry = &aria::gEmptyRoleMap;
+ }
+
+ } else if (frame->AccessibleType() == eHTMLTableCellType &&
+ aContext->ARIARoleMap() == &aria::gEmptyRoleMap) {
+ roleMapEntry = &aria::gEmptyRoleMap;
+
+ } else if (content->IsAnyOfHTMLElements(nsGkAtoms::dt, nsGkAtoms::li,
+ nsGkAtoms::dd) ||
+ frame->AccessibleType() == eHTMLLiType) {
+ const nsRoleMapEntry* contextRoleMap = aContext->ARIARoleMap();
+ if (!contextRoleMap->IsOfType(eList)) {
+ roleMapEntry = &aria::gEmptyRoleMap;
+ }
+ }
+ }
+ }
+
+ // XUL accessibles.
+ if (!newAcc && content->IsXULElement()) {
+ if (content->IsXULElement(nsGkAtoms::panel)) {
+ // We filter here instead of in the XUL map because
+ // if we filter there and return null, we still end up
+ // creating a generic accessible at the end of this function.
+ // Doing the filtering here ensures we never create accessibles
+ // for panels whose popups aren't visible.
+ nsMenuPopupFrame* popupFrame = do_QueryFrame(frame);
+ if (!popupFrame) {
+ return nullptr;
+ }
+
+ nsPopupState popupState = popupFrame->PopupState();
+ if (popupState == ePopupHiding || popupState == ePopupInvisible ||
+ popupState == ePopupClosed) {
+ return nullptr;
+ }
+ }
+
+ // Prefer to use XUL to decide if and what kind of accessible to create.
+ const XULMarkupMapInfo* xulMap =
+ mXULMarkupMap.Get(content->NodeInfo()->NameAtom());
+ if (xulMap && xulMap->new_func) {
+ newAcc = xulMap->new_func(content->AsElement(), aContext);
+ }
+
+ // Any XUL/flex box can be used as tabpanel, make sure we create a proper
+ // accessible for it.
+ if (!newAcc && aContext->IsXULTabpanels() &&
+ content->GetParent() == aContext->GetContent()) {
+ LayoutFrameType frameType = frame->Type();
+ // FIXME(emilio): Why only these frame types?
+ if (frameType == LayoutFrameType::FlexContainer ||
+ frameType == LayoutFrameType::Scroll) {
+ newAcc = new XULTabpanelAccessible(content, document);
+ }
+ }
+ }
+
+ if (!newAcc) {
+ if (content->IsSVGElement()) {
+ if (content->IsSVGGeometryElement() ||
+ content->IsSVGElement(nsGkAtoms::image)) {
+ // Shape elements: rect, circle, ellipse, line, path, polygon,
+ // and polyline. 'use' and 'text' graphic elements require
+ // special support.
+ if (MustSVGElementBeAccessible(content, document)) {
+ newAcc = new EnumRoleAccessible<roles::GRAPHIC>(content, document);
+ }
+ } else if (content->IsSVGElement(nsGkAtoms::text)) {
+ newAcc = new HyperTextAccessibleWrap(content->AsElement(), document);
+ } else if (content->IsSVGElement(nsGkAtoms::svg)) {
+ // An <svg> element could contain <foreignObject>, which contains HTML
+ // but does not normally create its own Accessible. This means that the
+ // <svg> Accessible could have TextLeafAccessible children, so it must
+ // be a HyperTextAccessible.
+ newAcc =
+ new EnumRoleHyperTextAccessible<roles::DIAGRAM>(content, document);
+ } else if (content->IsSVGElement(nsGkAtoms::g) &&
+ MustSVGElementBeAccessible(content, document)) {
+ // <g> can also contain <foreignObject>.
+ newAcc =
+ new EnumRoleHyperTextAccessible<roles::GROUPING>(content, document);
+ } else if (content->IsSVGElement(nsGkAtoms::a)) {
+ newAcc = new HTMLLinkAccessible(content, document);
+ }
+
+ } else if (content->IsMathMLElement()) {
+ const MarkupMapInfo* markupMap =
+ mMathMLMarkupMap.Get(content->NodeInfo()->NameAtom());
+ if (markupMap && markupMap->new_func) {
+ newAcc = markupMap->new_func(content->AsElement(), aContext);
+ }
+
+ // Fall back to text when encountering Content MathML.
+ if (!newAcc && !content->IsAnyOfMathMLElements(
+ nsGkAtoms::annotation_, nsGkAtoms::annotation_xml_,
+ nsGkAtoms::mpadded_, nsGkAtoms::mphantom_,
+ nsGkAtoms::maligngroup_, nsGkAtoms::malignmark_,
+ nsGkAtoms::mspace_, nsGkAtoms::semantics_)) {
+ newAcc = new HyperTextAccessibleWrap(content, document);
+ }
+ } else if (content->IsGeneratedContentContainerForMarker()) {
+ if (aContext->IsHTMLListItem()) {
+ newAcc = new HTMLListBulletAccessible(content, document);
+ }
+ if (aIsSubtreeHidden) {
+ *aIsSubtreeHidden = true;
+ }
+ }
+ }
+
+ // If no accessible, see if we need to create a generic accessible because
+ // of some property that makes this object interesting
+ // We don't do this for <body>, <html>, <window>, <dialog> etc. which
+ // correspond to the doc accessible and will be created in any case
+ if (!newAcc && !content->IsHTMLElement(nsGkAtoms::body) &&
+ content->GetParent() &&
+ (roleMapEntry || MustBeAccessible(content, document) ||
+ (content->IsHTMLElement() && nsCoreUtils::HasClickListener(content)))) {
+ // This content is focusable or has an interesting dynamic content
+ // accessibility property. If it's interesting we need it in the
+ // accessibility hierarchy so that events or other accessibles can point to
+ // it, or so that it can hold a state, etc.
+ if (content->IsHTMLElement() || content->IsMathMLElement()) {
+ // Interesting HTML/MathML container which may have selectable text and/or
+ // embedded objects
+ newAcc = new HyperTextAccessibleWrap(content, document);
+ } else { // XUL, SVG, etc.
+ // Interesting generic non-HTML container
+ newAcc = new AccessibleWrap(content, document);
+ }
+ } else if (!newAcc && MustBeGenericAccessible(content, document)) {
+ newAcc = new EnumRoleHyperTextAccessible<roles::TEXT_CONTAINER>(content,
+ document);
+ }
+
+ if (newAcc) {
+ document->BindToDocument(newAcc, roleMapEntry);
+ }
+ return newAcc;
+}
+
+#if defined(ANDROID)
+# include "mozilla/Monitor.h"
+# include "mozilla/Maybe.h"
+
+static Maybe<Monitor> sAndroidMonitor;
+
+mozilla::Monitor& nsAccessibilityService::GetAndroidMonitor() {
+ if (!sAndroidMonitor.isSome()) {
+ sAndroidMonitor.emplace("nsAccessibility::sAndroidMonitor");
+ }
+
+ return *sAndroidMonitor;
+}
+#endif
+
+////////////////////////////////////////////////////////////////////////////////
+// nsAccessibilityService private
+
+bool nsAccessibilityService::Init() {
+ AUTO_PROFILER_MARKER_TEXT("nsAccessibilityService::Init", A11Y, {}, ""_ns);
+ // DO NOT ADD CODE ABOVE HERE: THIS CODE IS MEASURING TIMINGS.
+
+ // Initialize accessible document manager.
+ if (!DocManager::Init()) return false;
+
+ // Add observers.
+ nsCOMPtr<nsIObserverService> observerService =
+ mozilla::services::GetObserverService();
+ if (!observerService) return false;
+
+ observerService->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
+
+#if defined(XP_WIN)
+ // This information needs to be initialized before the observer fires.
+ if (XRE_IsParentProcess()) {
+ Compatibility::Init();
+ }
+#endif // defined(XP_WIN)
+
+ // Subscribe to EventListenerService.
+ nsCOMPtr<nsIEventListenerService> eventListenerService =
+ do_GetService("@mozilla.org/eventlistenerservice;1");
+ if (!eventListenerService) return false;
+
+ eventListenerService->AddListenerChangeListener(this);
+
+ for (uint32_t i = 0; i < ArrayLength(sHTMLMarkupMapList); i++) {
+ mHTMLMarkupMap.InsertOrUpdate(sHTMLMarkupMapList[i].tag,
+ &sHTMLMarkupMapList[i]);
+ }
+ for (const auto& info : sMathMLMarkupMapList) {
+ mMathMLMarkupMap.InsertOrUpdate(info.tag, &info);
+ }
+
+ for (uint32_t i = 0; i < ArrayLength(sXULMarkupMapList); i++) {
+ mXULMarkupMap.InsertOrUpdate(sXULMarkupMapList[i].tag,
+ &sXULMarkupMapList[i]);
+ }
+
+#ifdef A11Y_LOG
+ logging::CheckEnv();
+#endif
+
+ gAccessibilityService = this;
+ NS_ADDREF(gAccessibilityService); // will release in Shutdown()
+
+ if (XRE_IsParentProcess()) {
+ gApplicationAccessible = new ApplicationAccessibleWrap();
+ } else {
+ gApplicationAccessible = new ApplicationAccessible();
+ }
+
+ NS_ADDREF(gApplicationAccessible); // will release in Shutdown()
+ gApplicationAccessible->Init();
+
+ CrashReporter::AnnotateCrashReport(CrashReporter::Annotation::Accessibility,
+ "Active"_ns);
+
+ // Now its safe to start platform accessibility.
+ if (XRE_IsParentProcess()) PlatformInit();
+
+ statistics::A11yInitialized();
+
+ static const char16_t kInitIndicator[] = {'1', 0};
+ observerService->NotifyObservers(nullptr, "a11y-init-or-shutdown",
+ kInitIndicator);
+
+ return true;
+}
+
+void nsAccessibilityService::Shutdown() {
+ // Application is going to be closed, shutdown accessibility and mark
+ // accessibility service as shutdown to prevent calls of its methods.
+ // Don't null accessibility service static member at this point to be safe
+ // if someone will try to operate with it.
+
+ MOZ_ASSERT(gConsumers, "Accessibility was shutdown already");
+ UnsetConsumers(eXPCOM | eMainProcess | ePlatformAPI);
+
+ // Remove observers.
+ nsCOMPtr<nsIObserverService> observerService =
+ mozilla::services::GetObserverService();
+ if (observerService) {
+ observerService->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
+ }
+
+ // Stop accessible document loader.
+ DocManager::Shutdown();
+
+ SelectionManager::Shutdown();
+
+ if (XRE_IsParentProcess()) PlatformShutdown();
+
+ gApplicationAccessible->Shutdown();
+ NS_RELEASE(gApplicationAccessible);
+ gApplicationAccessible = nullptr;
+
+ NS_IF_RELEASE(gXPCApplicationAccessible);
+ gXPCApplicationAccessible = nullptr;
+
+#if defined(ANDROID)
+ // Don't allow the service to shut down while an a11y request is being handled
+ // in the UI thread, as the request may depend on state from the service.
+ MonitorAutoLock mal(GetAndroidMonitor());
+#endif
+ NS_RELEASE(gAccessibilityService);
+ gAccessibilityService = nullptr;
+
+ if (observerService) {
+ static const char16_t kShutdownIndicator[] = {'0', 0};
+ observerService->NotifyObservers(nullptr, "a11y-init-or-shutdown",
+ kShutdownIndicator);
+ }
+}
+
+already_AddRefed<LocalAccessible>
+nsAccessibilityService::CreateAccessibleByFrameType(nsIFrame* aFrame,
+ nsIContent* aContent,
+ LocalAccessible* aContext) {
+ DocAccessible* document = aContext->Document();
+
+ RefPtr<LocalAccessible> newAcc;
+ switch (aFrame->AccessibleType()) {
+ case eNoType:
+ return nullptr;
+ case eHTMLBRType:
+ newAcc = new HTMLBRAccessible(aContent, document);
+ break;
+ case eHTMLButtonType:
+ newAcc = new HTMLButtonAccessible(aContent, document);
+ break;
+ case eHTMLCanvasType:
+ newAcc = new HTMLCanvasAccessible(aContent, document);
+ break;
+ case eHTMLCaptionType:
+ if (aContext->IsTable() &&
+ aContext->GetContent() == aContent->GetParent()) {
+ newAcc = new HTMLCaptionAccessible(aContent, document);
+ }
+ break;
+ case eHTMLCheckboxType:
+ newAcc = new CheckboxAccessible(aContent, document);
+ break;
+ case eHTMLComboboxType:
+ newAcc = new HTMLComboboxAccessible(aContent, document);
+ break;
+ case eHTMLFileInputType:
+ newAcc = new HTMLFileInputAccessible(aContent, document);
+ break;
+ case eHTMLGroupboxType:
+ newAcc = new HTMLGroupboxAccessible(aContent, document);
+ break;
+ case eHTMLHRType:
+ newAcc = new HTMLHRAccessible(aContent, document);
+ break;
+ case eHTMLImageMapType:
+ newAcc = new HTMLImageMapAccessible(aContent, document);
+ break;
+ case eHTMLLiType:
+ if (aContext->IsList() &&
+ aContext->GetContent() == aContent->GetParent()) {
+ newAcc = new HTMLLIAccessible(aContent, document);
+ } else {
+ // Otherwise create a generic text accessible to avoid text jamming.
+ newAcc = new HyperTextAccessibleWrap(aContent, document);
+ }
+ break;
+ case eHTMLSelectListType:
+ newAcc = new HTMLSelectListAccessible(aContent, document);
+ break;
+ case eHTMLMediaType:
+ newAcc = new EnumRoleAccessible<roles::GROUPING>(aContent, document);
+ break;
+ case eHTMLRadioButtonType:
+ newAcc = new HTMLRadioButtonAccessible(aContent, document);
+ break;
+ case eHTMLRangeType:
+ newAcc = new HTMLRangeAccessible(aContent, document);
+ break;
+ case eHTMLSpinnerType:
+ newAcc = new HTMLSpinnerAccessible(aContent, document);
+ break;
+ case eHTMLTableType:
+ case eHTMLTableCellType:
+ // We handle markup and ARIA tables elsewhere. If we reach here, this is
+ // a CSS table part. Just create a generic text container.
+ newAcc = new HyperTextAccessibleWrap(aContent, document);
+ break;
+ case eHTMLTableRowType:
+ // This is a CSS table row. Don't expose it at all.
+ break;
+ case eHTMLTextFieldType:
+ newAcc = new HTMLTextFieldAccessible(aContent, document);
+ break;
+ case eHyperTextType: {
+ if (aContext->IsTable() || aContext->IsTableRow()) {
+ // This is some generic hyperText, for example a block frame element
+ // inserted between a table and table row. Treat it as presentational.
+ return nullptr;
+ }
+
+ if (!aContent->IsAnyOfHTMLElements(nsGkAtoms::dt, nsGkAtoms::dd,
+ nsGkAtoms::div, nsGkAtoms::thead,
+ nsGkAtoms::tfoot, nsGkAtoms::tbody)) {
+ newAcc = new HyperTextAccessibleWrap(aContent, document);
+ }
+ break;
+ }
+ case eImageType:
+ if (aContent->IsElement() &&
+ ShouldCreateImgAccessible(aContent->AsElement(), document)) {
+ newAcc = new ImageAccessible(aContent, document);
+ }
+ break;
+ case eOuterDocType:
+ newAcc = new OuterDocAccessible(aContent, document);
+ break;
+ case eTextLeafType:
+ newAcc = new TextLeafAccessible(aContent, document);
+ break;
+ default:
+ MOZ_ASSERT(false);
+ break;
+ }
+
+ return newAcc.forget();
+}
+
+void nsAccessibilityService::MarkupAttributes(
+ Accessible* aAcc, AccAttributes* aAttributes) const {
+ const mozilla::a11y::MarkupMapInfo* markupMap = GetMarkupMapInfoFor(aAcc);
+ if (!markupMap) return;
+
+ dom::Element* el = aAcc->IsLocal() ? aAcc->AsLocal()->Elm() : nullptr;
+ for (uint32_t i = 0; i < ArrayLength(markupMap->attrs); i++) {
+ const MarkupAttrInfo* info = markupMap->attrs + i;
+ if (!info->name) break;
+
+ if (info->DOMAttrName) {
+ if (!el) {
+ // XXX Expose DOM attributes for cached RemoteAccessibles.
+ continue;
+ }
+ if (info->DOMAttrValue) {
+ if (el->AttrValueIs(kNameSpaceID_None, info->DOMAttrName,
+ info->DOMAttrValue, eCaseMatters)) {
+ aAttributes->SetAttribute(info->name, info->DOMAttrValue);
+ }
+ continue;
+ }
+
+ nsString value;
+ el->GetAttr(info->DOMAttrName, value);
+
+ if (!value.IsEmpty()) {
+ aAttributes->SetAttribute(info->name, std::move(value));
+ }
+
+ continue;
+ }
+
+ aAttributes->SetAttribute(info->name, info->value);
+ }
+}
+
+LocalAccessible* nsAccessibilityService::AddNativeRootAccessible(
+ void* aAtkAccessible) {
+#ifdef MOZ_ACCESSIBILITY_ATK
+ ApplicationAccessible* applicationAcc = ApplicationAcc();
+ if (!applicationAcc) return nullptr;
+
+ GtkWindowAccessible* nativeWnd =
+ new GtkWindowAccessible(static_cast<AtkObject*>(aAtkAccessible));
+
+ if (applicationAcc->AppendChild(nativeWnd)) return nativeWnd;
+#endif
+
+ return nullptr;
+}
+
+void nsAccessibilityService::RemoveNativeRootAccessible(
+ LocalAccessible* aAccessible) {
+#ifdef MOZ_ACCESSIBILITY_ATK
+ ApplicationAccessible* applicationAcc = ApplicationAcc();
+
+ if (applicationAcc) applicationAcc->RemoveChild(aAccessible);
+#endif
+}
+
+bool nsAccessibilityService::HasAccessible(nsINode* aDOMNode) {
+ if (!aDOMNode) return false;
+
+ Document* document = aDOMNode->OwnerDoc();
+ if (!document) return false;
+
+ DocAccessible* docAcc = GetExistingDocAccessible(aDOMNode->OwnerDoc());
+ if (!docAcc) return false;
+
+ return docAcc->HasAccessible(aDOMNode);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsAccessibilityService private (DON'T put methods here)
+
+void nsAccessibilityService::SetConsumers(uint32_t aConsumers, bool aNotify) {
+ if (gConsumers & aConsumers) {
+ return;
+ }
+
+ gConsumers |= aConsumers;
+ if (aNotify) {
+ NotifyOfConsumersChange();
+ }
+}
+
+void nsAccessibilityService::UnsetConsumers(uint32_t aConsumers) {
+ if (!(gConsumers & aConsumers)) {
+ return;
+ }
+
+ gConsumers &= ~aConsumers;
+ NotifyOfConsumersChange();
+}
+
+void nsAccessibilityService::GetConsumers(nsAString& aString) {
+ const char16_t* kJSONFmt =
+ u"{ \"XPCOM\": %s, \"MainProcess\": %s, \"PlatformAPI\": %s }";
+ nsString json;
+ nsTextFormatter::ssprintf(json, kJSONFmt,
+ gConsumers & eXPCOM ? "true" : "false",
+ gConsumers & eMainProcess ? "true" : "false",
+ gConsumers & ePlatformAPI ? "true" : "false");
+ aString.Assign(json);
+}
+
+void nsAccessibilityService::NotifyOfConsumersChange() {
+ nsCOMPtr<nsIObserverService> observerService =
+ mozilla::services::GetObserverService();
+
+ if (!observerService) {
+ return;
+ }
+
+ nsAutoString consumers;
+ GetConsumers(consumers);
+ observerService->NotifyObservers(nullptr, "a11y-consumers-changed",
+ consumers.get());
+}
+
+const mozilla::a11y::MarkupMapInfo* nsAccessibilityService::GetMarkupMapInfoFor(
+ Accessible* aAcc) const {
+ if (LocalAccessible* localAcc = aAcc->AsLocal()) {
+ return localAcc->HasOwnContent()
+ ? GetMarkupMapInfoFor(localAcc->GetContent())
+ : nullptr;
+ }
+ // XXX For now, we assume all RemoteAccessibles are HTML elements. This
+ // isn't strictly correct, but as far as current callers are concerned,
+ // this doesn't matter. If that changes in future, we could expose the
+ // element type via AccGenericType.
+ return mHTMLMarkupMap.Get(aAcc->TagName());
+}
+
+nsAccessibilityService* GetOrCreateAccService(uint32_t aNewConsumer) {
+ // Do not initialize accessibility if it is force disabled.
+ if (PlatformDisabledState() == ePlatformIsDisabled) {
+ return nullptr;
+ }
+
+ if (!nsAccessibilityService::gAccessibilityService) {
+ RefPtr<nsAccessibilityService> service = new nsAccessibilityService();
+ if (!service->Init()) {
+ service->Shutdown();
+ return nullptr;
+ }
+ }
+
+ MOZ_ASSERT(nsAccessibilityService::gAccessibilityService,
+ "LocalAccessible service is not initialized.");
+ nsAccessibilityService::gAccessibilityService->SetConsumers(aNewConsumer);
+ return nsAccessibilityService::gAccessibilityService;
+}
+
+void MaybeShutdownAccService(uint32_t aFormerConsumer) {
+ nsAccessibilityService* accService =
+ nsAccessibilityService::gAccessibilityService;
+
+ if (!accService || nsAccessibilityService::IsShutdown()) {
+ return;
+ }
+
+ // Still used by XPCOM
+ if (nsCoreUtils::AccEventObserversExist() ||
+ xpcAccessibilityService::IsInUse() || accService->HasXPCDocuments()) {
+ // In case the XPCOM flag was unset (possibly because of the shutdown
+ // timer in the xpcAccessibilityService) ensure it is still present. Note:
+ // this should be fixed when all the consumer logic is taken out as a
+ // separate class.
+ accService->SetConsumers(nsAccessibilityService::eXPCOM, false);
+
+ if (aFormerConsumer != nsAccessibilityService::eXPCOM) {
+ // Only unset non-XPCOM consumers.
+ accService->UnsetConsumers(aFormerConsumer);
+ }
+ return;
+ }
+
+ if (nsAccessibilityService::gConsumers & ~aFormerConsumer) {
+ accService->UnsetConsumers(aFormerConsumer);
+ } else {
+ accService
+ ->Shutdown(); // Will unset all nsAccessibilityService::gConsumers
+ }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Services
+////////////////////////////////////////////////////////////////////////////////
+
+namespace mozilla {
+namespace a11y {
+
+FocusManager* FocusMgr() {
+ return nsAccessibilityService::gAccessibilityService;
+}
+
+SelectionManager* SelectionMgr() {
+ return nsAccessibilityService::gAccessibilityService;
+}
+
+ApplicationAccessible* ApplicationAcc() {
+ return nsAccessibilityService::gApplicationAccessible;
+}
+
+xpcAccessibleApplication* XPCApplicationAcc() {
+ if (!nsAccessibilityService::gXPCApplicationAccessible &&
+ nsAccessibilityService::gApplicationAccessible) {
+ nsAccessibilityService::gXPCApplicationAccessible =
+ new xpcAccessibleApplication(
+ nsAccessibilityService::gApplicationAccessible);
+ NS_ADDREF(nsAccessibilityService::gXPCApplicationAccessible);
+ }
+
+ return nsAccessibilityService::gXPCApplicationAccessible;
+}
+
+EPlatformDisabledState PlatformDisabledState() {
+ static bool platformDisabledStateCached = false;
+ if (platformDisabledStateCached) {
+ return static_cast<EPlatformDisabledState>(sPlatformDisabledState);
+ }
+
+ platformDisabledStateCached = true;
+ Preferences::RegisterCallback(PrefChanged, PREF_ACCESSIBILITY_FORCE_DISABLED);
+ return ReadPlatformDisabledState();
+}
+
+EPlatformDisabledState ReadPlatformDisabledState() {
+ sPlatformDisabledState =
+ Preferences::GetInt(PREF_ACCESSIBILITY_FORCE_DISABLED, 0);
+ if (sPlatformDisabledState < ePlatformIsForceEnabled) {
+ sPlatformDisabledState = ePlatformIsForceEnabled;
+ } else if (sPlatformDisabledState > ePlatformIsDisabled) {
+ sPlatformDisabledState = ePlatformIsDisabled;
+ }
+
+ return static_cast<EPlatformDisabledState>(sPlatformDisabledState);
+}
+
+void PrefChanged(const char* aPref, void* aClosure) {
+ if (ReadPlatformDisabledState() == ePlatformIsDisabled) {
+ // Force shut down accessibility.
+ nsAccessibilityService* accService =
+ nsAccessibilityService::gAccessibilityService;
+ if (accService && !nsAccessibilityService::IsShutdown()) {
+ accService->Shutdown();
+ }
+ }
+}
+
+} // namespace a11y
+} // namespace mozilla