AXIsolatedTree.cpp [plain text]
#include "config.h"
#if ENABLE(ACCESSIBILITY_ISOLATED_TREE)
#include "AXIsolatedTree.h"
#include "AXIsolatedObject.h"
#include "AXLogger.h"
#include "Page.h"
#include <wtf/NeverDestroyed.h>
namespace WebCore {
static Lock s_cacheLock;
static unsigned newTreeID()
{
static unsigned s_currentTreeID = 0;
return ++s_currentTreeID;
}
HashMap<PageIdentifier, Ref<AXIsolatedTree>>& AXIsolatedTree::treePageCache()
{
static NeverDestroyed<HashMap<PageIdentifier, Ref<AXIsolatedTree>>> map;
return map;
}
HashMap<AXIsolatedTreeID, Ref<AXIsolatedTree>>& AXIsolatedTree::treeIDCache()
{
static NeverDestroyed<HashMap<AXIsolatedTreeID, Ref<AXIsolatedTree>>> map;
return map;
}
AXIsolatedTree::AXIsolatedTree(AXObjectCache* axObjectCache)
: m_treeID(newTreeID())
, m_axObjectCache(axObjectCache)
, m_usedOnAXThread(axObjectCache->usedOnAXThread())
{
AXTRACE("AXIsolatedTree::AXIsolatedTree");
ASSERT(isMainThread());
}
AXIsolatedTree::~AXIsolatedTree()
{
AXTRACE("AXIsolatedTree::~AXIsolatedTree");
}
void AXIsolatedTree::clear()
{
AXTRACE("AXIsolatedTree::clear");
ASSERT(isMainThread());
m_axObjectCache = nullptr;
LockHolder locker { m_changeLogLock };
m_pendingSubtreeRemovals.append(m_rootNode->objectID());
m_rootNode = nullptr;
m_nodeMap.clear();
}
RefPtr<AXIsolatedTree> AXIsolatedTree::treeForID(AXIsolatedTreeID treeID)
{
AXTRACE("AXIsolatedTree::treeForID");
return treeIDCache().get(treeID);
}
Ref<AXIsolatedTree> AXIsolatedTree::create(AXObjectCache* axObjectCache)
{
AXTRACE("AXIsolatedTree::create");
ASSERT(isMainThread());
ASSERT(axObjectCache && axObjectCache->pageID());
auto tree = adoptRef(*new AXIsolatedTree(axObjectCache));
auto* axRoot = axObjectCache->getOrCreate(axObjectCache->document().view());
if (axRoot)
tree->generateSubtree(*axRoot, nullptr, true);
auto* axFocus = axObjectCache->focusedObjectForPage(axObjectCache->document().page());
if (axFocus)
tree->setFocusedNodeID(axFocus->objectID());
auto pageID = axObjectCache->pageID();
LockHolder locker(s_cacheLock);
ASSERT(!treePageCache().contains(*pageID));
treePageCache().set(*pageID, tree.copyRef());
treeIDCache().set(tree->treeID(), tree.copyRef());
return tree;
}
void AXIsolatedTree::removeTreeForPageID(PageIdentifier pageID)
{
AXTRACE("AXIsolatedTree::removeTreeForPageID");
ASSERT(isMainThread());
LockHolder locker(s_cacheLock);
if (auto tree = treePageCache().take(pageID)) {
tree->clear();
treeIDCache().remove(tree->treeID());
}
}
RefPtr<AXIsolatedTree> AXIsolatedTree::treeForPageID(PageIdentifier pageID)
{
LockHolder locker(s_cacheLock);
if (auto tree = treePageCache().get(pageID))
return makeRefPtr(tree);
return nullptr;
}
RefPtr<AXIsolatedObject> AXIsolatedTree::nodeForID(AXID axID) const
{
if (m_usedOnAXThread && isMainThread())
return nullptr;
return axID != InvalidAXID ? m_readerThreadNodeMap.get(axID) : nullptr;
}
Vector<RefPtr<AXCoreObject>> AXIsolatedTree::objectsForIDs(const Vector<AXID>& axIDs) const
{
AXTRACE("AXIsolatedTree::objectsForIDs");
Vector<RefPtr<AXCoreObject>> result;
result.reserveCapacity(axIDs.size());
for (const auto& axID : axIDs) {
if (auto object = nodeForID(axID))
result.uncheckedAppend(object);
}
return result;
}
Vector<AXID> AXIsolatedTree::idsForObjects(const Vector<RefPtr<AXCoreObject>>& objects) const
{
return objects.map([] (const RefPtr<AXCoreObject>& object) -> AXID {
return object ? object->objectID() : InvalidAXID;
});
}
void AXIsolatedTree::updateChildrenIDs(AXID axID, Vector<AXID>&& childrenIDs)
{
ASSERT(isMainThread());
ASSERT(m_changeLogLock.isLocked());
if (axID != InvalidAXID) {
m_nodeMap.set(axID, childrenIDs);
m_pendingChildrenUpdates.append(std::make_pair(axID, WTFMove(childrenIDs)));
}
}
void AXIsolatedTree::generateSubtree(AXCoreObject& axObject, AXCoreObject* axParent, bool attachWrapper)
{
AXTRACE("AXIsolatedTree::generateSubtree");
ASSERT(isMainThread());
if (axObject.objectID() == InvalidAXID)
return;
auto object = createSubtree(axObject, axParent ? axParent->objectID() : InvalidAXID, attachWrapper);
LockHolder locker { m_changeLogLock };
if (!axParent)
setRootNode(object.ptr());
else if (axParent->objectID() != InvalidAXID) updateChildrenIDs(axParent->objectID(), axParent->childrenIDs());
}
Ref<AXIsolatedObject> AXIsolatedTree::createSubtree(AXCoreObject& axObject, AXID parentID, bool attachWrapper)
{
AXTRACE("AXIsolatedTree::createSubtree");
ASSERT(isMainThread());
auto object = AXIsolatedObject::create(axObject, this, parentID);
if (object->objectID() == InvalidAXID) {
ASSERT_NOT_REACHED();
return object;
}
NodeChange nodeChange { object, nullptr };
if (attachWrapper)
object->attachPlatformWrapper(axObject.wrapper());
else {
nodeChange.wrapper = axObject.wrapper();
}
auto axChildren = axObject.children();
Vector<AXID> childrenIDs;
childrenIDs.reserveCapacity(axChildren.size());
for (const auto& axChild : axChildren) {
auto child = createSubtree(*axChild, axObject.objectID(), attachWrapper);
childrenIDs.uncheckedAppend(child->objectID());
}
{
LockHolder locker { m_changeLogLock };
m_pendingAppends.append(WTFMove(nodeChange));
updateChildrenIDs(object->objectID(), WTFMove(childrenIDs));
}
return object;
}
void AXIsolatedTree::updateNode(AXCoreObject& axObject)
{
AXTRACE("AXIsolatedTree::updateNode");
AXLOG(&axObject);
ASSERT(isMainThread());
AXID axID = axObject.objectID();
auto* axParent = axObject.parentObject();
AXID parentID = axParent ? axParent->objectID() : InvalidAXID;
auto newObject = AXIsolatedObject::create(axObject, this, parentID);
newObject->m_childrenIDs = axObject.childrenIDs();
LockHolder locker { m_changeLogLock };
m_pendingNodeRemovals.append(axID);
m_pendingAppends.append({ newObject, axObject.wrapper() });
}
void AXIsolatedTree::updateNodeProperty(const AXCoreObject& axObject, AXPropertyName property)
{
AXTRACE("AXIsolatedTree::updateNodeProperty");
ASSERT(isMainThread());
AXPropertyMap propertyMap;
switch (property) {
case AXPropertyName::IsChecked:
propertyMap.set(AXPropertyName::IsChecked, axObject.isChecked());
break;
case AXPropertyName::SortDirection:
propertyMap.set(AXPropertyName::SortDirection, static_cast<int>(axObject.sortDirection()));
break;
case AXPropertyName::IdentifierAttribute:
propertyMap.set(AXPropertyName::IdentifierAttribute, axObject.identifierAttribute().isolatedCopy());
break;
default:
return;
}
LockHolder locker { m_changeLogLock };
m_pendingPropertyChanges.append({ axObject.objectID(), propertyMap });
}
void AXIsolatedTree::updateSubtree(AXCoreObject& axObject)
{
AXTRACE("AXIsolatedTree::updateSubtree");
AXLOG(&axObject);
ASSERT(isMainThread());
removeSubtree(axObject.objectID());
generateSubtree(axObject, axObject.parentObject(), false);
}
void AXIsolatedTree::updateChildren(AXCoreObject& axObject)
{
AXTRACE("AXIsolatedTree::updateChildren");
AXLOG("For AXObject:");
AXLOG(&axObject);
ASSERT(isMainThread());
if (m_nodeMap.isEmpty()) {
ASSERT_NOT_REACHED();
return;
}
if (!axObject.document() || !axObject.document()->hasLivingRenderTree())
return;
auto iterator = m_nodeMap.end();
auto* axAncestor = Accessibility::findAncestor(axObject, true, [&iterator, this] (const AXCoreObject& ancestor) {
auto it = m_nodeMap.find(ancestor.objectID());
if (it != m_nodeMap.end()) {
iterator = it;
return true;
}
return false;
});
if (!axAncestor || axAncestor->objectID() == InvalidAXID || iterator == m_nodeMap.end()) {
return;
}
ASSERT(iterator->key == axAncestor->objectID());
auto removals = iterator->value;
const auto& axChildren = axAncestor->children();
auto axChildrenIDs = axAncestor->childrenIDs();
bool updatedChild = false; for (size_t i = 0; i < axChildren.size() && i < axChildrenIDs.size(); ++i) {
size_t index = removals.find(axChildrenIDs[i]);
if (index != notFound)
removals.remove(index);
else {
ASSERT(axChildren[i]->objectID() == axChildrenIDs[i]);
AXLOG("Adding a new child for:");
AXLOG(axChildren[i]);
generateSubtree(*axChildren[i], axAncestor, true);
updatedChild = true;
}
}
for (const AXID& childID : removals)
removeSubtree(childID);
if (updatedChild || removals.size()) {
LockHolder locker { m_changeLogLock };
updateChildrenIDs(axAncestor->objectID(), WTFMove(axChildrenIDs));
} else {
updateSubtree(*axAncestor);
}
}
RefPtr<AXIsolatedObject> AXIsolatedTree::focusedNode()
{
AXTRACE("AXIsolatedTree::focusedNode");
applyPendingChanges();
LockHolder locker { m_changeLogLock };
AXLOG(makeString("focusedNodeID ", m_focusedNodeID));
AXLOG("focused node:");
AXLOG(nodeForID(m_focusedNodeID));
return nodeForID(m_focusedNodeID);
}
RefPtr<AXIsolatedObject> AXIsolatedTree::rootNode()
{
AXTRACE("AXIsolatedTree::rootNode");
LockHolder locker { m_changeLogLock };
return m_rootNode;
}
void AXIsolatedTree::setRootNode(AXIsolatedObject* root)
{
AXTRACE("AXIsolatedTree::setRootNode");
ASSERT(isMainThread());
ASSERT(m_changeLogLock.isLocked());
ASSERT(!m_rootNode);
ASSERT(root);
m_rootNode = root;
}
void AXIsolatedTree::setFocusedNodeID(AXID axID)
{
AXTRACE("AXIsolatedTree::setFocusedNodeID");
AXLOG(makeString("axID ", axID));
ASSERT(isMainThread());
LockHolder locker { m_changeLogLock };
m_pendingFocusedNodeID = axID;
AXPropertyMap propertyMap;
propertyMap.set(AXPropertyName::IsFocused, true);
m_pendingPropertyChanges.append({ axID, propertyMap });
}
void AXIsolatedTree::removeNode(AXID axID)
{
AXTRACE("AXIsolatedTree::removeNode");
AXLOG(makeString("AXID ", axID));
ASSERT(isMainThread());
m_nodeMap.remove(axID);
LockHolder locker { m_changeLogLock };
m_pendingNodeRemovals.append(axID);
}
void AXIsolatedTree::removeSubtree(AXID axID)
{
AXTRACE("AXIsolatedTree::removeSubtree");
AXLOG(makeString("Removing subtree for axID ", axID));
ASSERT(isMainThread());
Vector<AXID> removals = { axID };
while (removals.size()) {
AXID axID = removals.takeLast();
if (axID == InvalidAXID)
continue;
auto it = m_nodeMap.find(axID);
if (it != m_nodeMap.end()) {
removals.appendVector(it->value);
m_nodeMap.remove(axID);
}
}
LockHolder locker { m_changeLogLock };
m_pendingSubtreeRemovals.append(axID);
}
void AXIsolatedTree::applyPendingChanges()
{
AXTRACE("AXIsolatedTree::applyPendingChanges");
if (m_usedOnAXThread && isMainThread())
return;
LockHolder locker { m_changeLogLock };
if (m_pendingFocusedNodeID != m_focusedNodeID) {
AXLOG(makeString("focusedNodeID ", m_focusedNodeID, " pendingFocusedNodeID ", m_pendingFocusedNodeID));
if (m_focusedNodeID != InvalidAXID) {
AXPropertyMap propertyMap;
propertyMap.set(AXPropertyName::IsFocused, false);
m_pendingPropertyChanges.append({ m_focusedNodeID, propertyMap });
}
m_focusedNodeID = m_pendingFocusedNodeID;
}
while (m_pendingNodeRemovals.size()) {
auto axID = m_pendingNodeRemovals.takeLast();
AXLOG(makeString("removing axID ", axID));
if (auto object = nodeForID(axID)) {
object->detach(AccessibilityDetachmentType::ElementDestroyed);
m_readerThreadNodeMap.remove(axID);
}
}
while (m_pendingSubtreeRemovals.size()) {
auto axID = m_pendingSubtreeRemovals.takeLast();
AXLOG(makeString("removing subtree axID ", axID));
if (auto object = nodeForID(axID)) {
object->detach(AccessibilityDetachmentType::ElementDestroyed);
m_pendingSubtreeRemovals.appendVector(object->m_childrenIDs);
m_readerThreadNodeMap.remove(axID);
}
}
for (const auto& item : m_pendingAppends) {
AXID axID = item.isolatedObject->objectID();
AXLOG(makeString("appending axID ", axID));
if (axID == InvalidAXID)
continue;
auto& wrapper = item.wrapper ? item.wrapper : item.isolatedObject->wrapper();
if (!wrapper)
continue;
if (auto object = m_readerThreadNodeMap.get(axID)) {
if (object != &item.isolatedObject.get()
&& object->wrapper() == wrapper.get()) {
object->detachWrapper(AccessibilityDetachmentType::ElementChanged);
item.isolatedObject->attachPlatformWrapper(wrapper.get());
}
m_readerThreadNodeMap.remove(axID);
}
if (!item.isolatedObject->wrapper()) {
item.isolatedObject->attachPlatformWrapper(wrapper.get());
}
auto addResult = m_readerThreadNodeMap.add(axID, item.isolatedObject.get());
ASSERT_UNUSED(addResult, addResult.iterator->value->wrapper());
ASSERT_UNUSED(addResult, addResult.iterator->value->refCount() == 2
|| (addResult.iterator->value.ptr() == m_rootNode.get() && m_rootNode->refCount() == 3));
}
m_pendingAppends.clear();
for (auto& update : m_pendingChildrenUpdates) {
AXLOG(makeString("updating children for axID ", update.first));
if (auto object = nodeForID(update.first))
object->m_childrenIDs = WTFMove(update.second);
}
m_pendingChildrenUpdates.clear();
for (auto& change : m_pendingPropertyChanges) {
if (auto object = nodeForID(change.axID)) {
for (auto& property : change.properties)
object->setProperty(property.key, WTFMove(property.value));
}
}
m_pendingPropertyChanges.clear();
}
}
#endif // ENABLE(ACCESSIBILITY_ISOLATED_TREE)