gecko/accessible/base/NotificationController.cpp
Trevor Saunders 0ec2314a66 bug 1088148 - Notify the main process of new child docs after firing events r=davidb
If we notify the parent process about new child documents before we
notify it of events it is possible the parent process's tree is out of
sync with ours, and doesn't contain the outer doc accessible for the new
document.  SO we need to first notify the parent of changes in the
accessible tree for the document, and then we can notify it of new child
documents.  We must also make sure when we serialize a subtree that is
being created to not include the sub document or its accessible tree.
2014-10-28 14:18:03 -04:00

448 lines
15 KiB
C++

/* -*- 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 "NotificationController.h"
#include "DocAccessible-inl.h"
#include "DocAccessibleChild.h"
#include "TextLeafAccessible.h"
#include "TextUpdater.h"
#include "mozilla/dom/ContentChild.h"
#include "mozilla/dom/Element.h"
#include "mozilla/Telemetry.h"
using namespace mozilla;
using namespace mozilla::a11y;
////////////////////////////////////////////////////////////////////////////////
// NotificationCollector
////////////////////////////////////////////////////////////////////////////////
NotificationController::NotificationController(DocAccessible* aDocument,
nsIPresShell* aPresShell) :
EventQueue(aDocument), mObservingState(eNotObservingRefresh),
mPresShell(aPresShell)
{
// Schedule initial accessible tree construction.
ScheduleProcessing();
}
NotificationController::~NotificationController()
{
NS_ASSERTION(!mDocument, "Controller wasn't shutdown properly!");
if (mDocument)
Shutdown();
}
////////////////////////////////////////////////////////////////////////////////
// NotificationCollector: AddRef/Release and cycle collection
NS_IMPL_CYCLE_COLLECTING_NATIVE_ADDREF(NotificationController)
NS_IMPL_CYCLE_COLLECTING_NATIVE_RELEASE(NotificationController)
NS_IMPL_CYCLE_COLLECTION_CLASS(NotificationController)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(NotificationController)
if (tmp->mDocument)
tmp->Shutdown();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(NotificationController)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mHangingChildDocuments)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mContentInsertions)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEvents)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(NotificationController, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(NotificationController, Release)
////////////////////////////////////////////////////////////////////////////////
// NotificationCollector: public
void
NotificationController::Shutdown()
{
if (mObservingState != eNotObservingRefresh &&
mPresShell->RemoveRefreshObserver(this, Flush_Display)) {
mObservingState = eNotObservingRefresh;
}
// Shutdown handling child documents.
int32_t childDocCount = mHangingChildDocuments.Length();
for (int32_t idx = childDocCount - 1; idx >= 0; idx--) {
if (!mHangingChildDocuments[idx]->IsDefunct())
mHangingChildDocuments[idx]->Shutdown();
}
mHangingChildDocuments.Clear();
mDocument = nullptr;
mPresShell = nullptr;
mTextHash.Clear();
mContentInsertions.Clear();
mNotifications.Clear();
mEvents.Clear();
}
void
NotificationController::ScheduleChildDocBinding(DocAccessible* aDocument)
{
// Schedule child document binding to the tree.
mHangingChildDocuments.AppendElement(aDocument);
ScheduleProcessing();
}
void
NotificationController::ScheduleContentInsertion(Accessible* aContainer,
nsIContent* aStartChildNode,
nsIContent* aEndChildNode)
{
nsRefPtr<ContentInsertion> insertion = new ContentInsertion(mDocument,
aContainer);
if (insertion && insertion->InitChildList(aStartChildNode, aEndChildNode) &&
mContentInsertions.AppendElement(insertion)) {
ScheduleProcessing();
}
}
////////////////////////////////////////////////////////////////////////////////
// NotificationCollector: protected
void
NotificationController::ScheduleProcessing()
{
// If notification flush isn't planed yet start notification flush
// asynchronously (after style and layout).
if (mObservingState == eNotObservingRefresh) {
if (mPresShell->AddRefreshObserver(this, Flush_Display))
mObservingState = eRefreshObserving;
}
}
bool
NotificationController::IsUpdatePending()
{
return mPresShell->IsLayoutFlushObserver() ||
mObservingState == eRefreshProcessingForUpdate ||
mContentInsertions.Length() != 0 || mNotifications.Length() != 0 ||
mTextHash.Count() != 0 ||
!mDocument->HasLoadState(DocAccessible::eTreeConstructed);
}
////////////////////////////////////////////////////////////////////////////////
// NotificationCollector: private
void
NotificationController::WillRefresh(mozilla::TimeStamp aTime)
{
Telemetry::AutoTimer<Telemetry::A11Y_UPDATE_TIME> updateTimer;
// If the document accessible that notification collector was created for is
// now shut down, don't process notifications anymore.
NS_ASSERTION(mDocument,
"The document was shut down while refresh observer is attached!");
if (!mDocument)
return;
if (mObservingState == eRefreshProcessing ||
mObservingState == eRefreshProcessingForUpdate)
return;
// Any generic notifications should be queued if we're processing content
// insertions or generic notifications.
mObservingState = eRefreshProcessingForUpdate;
// Initial accessible tree construction.
if (!mDocument->HasLoadState(DocAccessible::eTreeConstructed)) {
// If document is not bound to parent at this point then the document is not
// ready yet (process notifications later).
if (!mDocument->IsBoundToParent()) {
mObservingState = eRefreshObserving;
return;
}
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eTree)) {
logging::MsgBegin("TREE", "initial tree created");
logging::Address("document", mDocument);
logging::MsgEnd();
}
#endif
mDocument->DoInitialUpdate();
NS_ASSERTION(mContentInsertions.Length() == 0,
"Pending content insertions while initial accessible tree isn't created!");
}
// Initialize scroll support if needed.
if (!(mDocument->mDocFlags & DocAccessible::eScrollInitialized))
mDocument->AddScrollListener();
// Process content inserted notifications to update the tree. Process other
// notifications like DOM events and then flush event queue. If any new
// notifications are queued during this processing then they will be processed
// on next refresh. If notification processing queues up new events then they
// are processed in this refresh. If events processing queues up new events
// then new events are processed on next refresh.
// Note: notification processing or event handling may shut down the owning
// document accessible.
// Process only currently queued content inserted notifications.
nsTArray<nsRefPtr<ContentInsertion> > contentInsertions;
contentInsertions.SwapElements(mContentInsertions);
uint32_t insertionCount = contentInsertions.Length();
for (uint32_t idx = 0; idx < insertionCount; idx++) {
contentInsertions[idx]->Process();
if (!mDocument)
return;
}
// Process rendered text change notifications.
mTextHash.EnumerateEntries(TextEnumerator, mDocument);
mTextHash.Clear();
// Bind hanging child documents.
uint32_t hangingDocCnt = mHangingChildDocuments.Length();
for (uint32_t idx = 0; idx < hangingDocCnt; idx++) {
DocAccessible* childDoc = mHangingChildDocuments[idx];
if (childDoc->IsDefunct())
continue;
nsIContent* ownerContent = mDocument->DocumentNode()->
FindContentForSubDocument(childDoc->DocumentNode());
if (ownerContent) {
Accessible* outerDocAcc = mDocument->GetAccessible(ownerContent);
if (outerDocAcc && outerDocAcc->AppendChild(childDoc)) {
if (mDocument->AppendChildDocument(childDoc)) {
continue;
}
outerDocAcc->RemoveChild(childDoc);
}
// Failed to bind the child document, destroy it.
childDoc->Shutdown();
}
}
nsTArray<nsRefPtr<DocAccessible>> newChildDocs = Move(mHangingChildDocuments);
// If the document is ready and all its subdocuments are completely loaded
// then process the document load.
if (mDocument->HasLoadState(DocAccessible::eReady) &&
!mDocument->HasLoadState(DocAccessible::eCompletelyLoaded) &&
hangingDocCnt == 0) {
uint32_t childDocCnt = mDocument->ChildDocumentCount(), childDocIdx = 0;
for (; childDocIdx < childDocCnt; childDocIdx++) {
DocAccessible* childDoc = mDocument->GetChildDocumentAt(childDocIdx);
if (!childDoc->HasLoadState(DocAccessible::eCompletelyLoaded))
break;
}
if (childDocIdx == childDocCnt) {
mDocument->ProcessLoad();
if (!mDocument)
return;
}
}
// Process only currently queued generic notifications.
nsTArray < nsRefPtr<Notification> > notifications;
notifications.SwapElements(mNotifications);
uint32_t notificationCount = notifications.Length();
for (uint32_t idx = 0; idx < notificationCount; idx++) {
notifications[idx]->Process();
if (!mDocument)
return;
}
// Process invalidation list of the document after all accessible tree
// modification are done.
mDocument->ProcessInvalidationList();
// If a generic notification occurs after this point then we may be allowed to
// process it synchronously. However we do not want to reenter if fireing
// events causes script to run.
mObservingState = eRefreshProcessing;
ProcessEventQueue();
if (IPCAccessibilityActive()) {
size_t newDocCount = newChildDocs.Length();
for (size_t i = 0; i < newDocCount; i++) {
DocAccessible* childDoc = newChildDocs[i];
DocAccessibleChild* ipcDoc = new DocAccessibleChild(childDoc);
childDoc->SetIPCDoc(ipcDoc);
auto contentChild = dom::ContentChild::GetSingleton();
DocAccessibleChild* parentIPCDoc = mDocument->IPCDoc();
uint64_t id = reinterpret_cast<uintptr_t>(childDoc->Parent()->UniqueID());
contentChild->SendPDocAccessibleConstructor(ipcDoc, parentIPCDoc, id);
}
}
mObservingState = eRefreshObserving;
if (!mDocument)
return;
// Stop further processing if there are no new notifications of any kind or
// events and document load is processed.
if (mContentInsertions.IsEmpty() && mNotifications.IsEmpty() &&
mEvents.IsEmpty() && mTextHash.Count() == 0 &&
mHangingChildDocuments.IsEmpty() &&
mDocument->HasLoadState(DocAccessible::eCompletelyLoaded) &&
mPresShell->RemoveRefreshObserver(this, Flush_Display)) {
mObservingState = eNotObservingRefresh;
}
}
////////////////////////////////////////////////////////////////////////////////
// Notification controller: text leaf accessible text update
PLDHashOperator
NotificationController::TextEnumerator(nsCOMPtrHashKey<nsIContent>* aEntry,
void* aUserArg)
{
DocAccessible* document = static_cast<DocAccessible*>(aUserArg);
nsIContent* textNode = aEntry->GetKey();
Accessible* textAcc = document->GetAccessible(textNode);
// If the text node is not in tree or doesn't have frame then this case should
// have been handled already by content removal notifications.
nsINode* containerNode = textNode->GetParentNode();
if (!containerNode) {
NS_ASSERTION(!textAcc,
"Text node was removed but accessible is kept alive!");
return PL_DHASH_NEXT;
}
nsIFrame* textFrame = textNode->GetPrimaryFrame();
if (!textFrame) {
NS_ASSERTION(!textAcc,
"Text node isn't rendered but accessible is kept alive!");
return PL_DHASH_NEXT;
}
nsIContent* containerElm = containerNode->IsElement() ?
containerNode->AsElement() : nullptr;
nsAutoString text;
textFrame->GetRenderedText(&text);
// Remove text accessible if rendered text is empty.
if (textAcc) {
if (text.IsEmpty()) {
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eTree | logging::eText)) {
logging::MsgBegin("TREE", "text node lost its content");
logging::Node("container", containerElm);
logging::Node("content", textNode);
logging::MsgEnd();
}
#endif
document->ContentRemoved(containerElm, textNode);
return PL_DHASH_NEXT;
}
// Update text of the accessible and fire text change events.
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eText)) {
logging::MsgBegin("TEXT", "text may be changed");
logging::Node("container", containerElm);
logging::Node("content", textNode);
logging::MsgEntry("old text '%s'",
NS_ConvertUTF16toUTF8(textAcc->AsTextLeaf()->Text()).get());
logging::MsgEntry("new text: '%s'",
NS_ConvertUTF16toUTF8(text).get());
logging::MsgEnd();
}
#endif
TextUpdater::Run(document, textAcc->AsTextLeaf(), text);
return PL_DHASH_NEXT;
}
// Append an accessible if rendered text is not empty.
if (!text.IsEmpty()) {
#ifdef A11Y_LOG
if (logging::IsEnabled(logging::eTree | logging::eText)) {
logging::MsgBegin("TREE", "text node gains new content");
logging::Node("container", containerElm);
logging::Node("content", textNode);
logging::MsgEnd();
}
#endif
// Make sure the text node is in accessible document still.
Accessible* container = document->GetAccessibleOrContainer(containerNode);
NS_ASSERTION(container,
"Text node having rendered text hasn't accessible document!");
if (container) {
nsTArray<nsCOMPtr<nsIContent> > insertedContents;
insertedContents.AppendElement(textNode);
document->ProcessContentInserted(container, &insertedContents);
}
}
return PL_DHASH_NEXT;
}
////////////////////////////////////////////////////////////////////////////////
// NotificationController: content inserted notification
NotificationController::ContentInsertion::
ContentInsertion(DocAccessible* aDocument, Accessible* aContainer) :
mDocument(aDocument), mContainer(aContainer)
{
}
bool
NotificationController::ContentInsertion::
InitChildList(nsIContent* aStartChildNode, nsIContent* aEndChildNode)
{
bool haveToUpdate = false;
nsIContent* node = aStartChildNode;
while (node != aEndChildNode) {
// Notification triggers for content insertion even if no content was
// actually inserted, check if the given content has a frame to discard
// this case early.
if (node->GetPrimaryFrame()) {
if (mInsertedContent.AppendElement(node))
haveToUpdate = true;
}
node = node->GetNextSibling();
}
return haveToUpdate;
}
NS_IMPL_CYCLE_COLLECTION(NotificationController::ContentInsertion,
mContainer)
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(NotificationController::ContentInsertion,
AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(NotificationController::ContentInsertion,
Release)
void
NotificationController::ContentInsertion::Process()
{
mDocument->ProcessContentInserted(mContainer, &mInsertedContent);
mDocument = nullptr;
mContainer = nullptr;
mInsertedContent.Clear();
}