Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 601 insertions, 0 deletions

diff --git a/accessible/base/EventTree.cpp b/accessible/base/EventTree.cpp
new file mode 100644
index 0000000000..f804275775
--- /dev/null
+++ b/accessible/base/EventTree.cpp
@@ -0,0 +1,601 @@
+/* -*- 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 "EventTree.h"
+
+#include "Accessible-inl.h"
+#include "EmbeddedObjCollector.h"
+#include "NotificationController.h"
+#include "nsEventShell.h"
+#include "DocAccessible.h"
+#ifdef A11Y_LOG
+#  include "Logging.h"
+#endif
+
+#include "mozilla/UniquePtr.h"
+
+using namespace mozilla;
+using namespace mozilla::a11y;
+
+////////////////////////////////////////////////////////////////////////////////
+// TreeMutation class
+
+EventTree* const TreeMutation::kNoEventTree = reinterpret_cast<EventTree*>(-1);
+
+TreeMutation::TreeMutation(Accessible* aParent, bool aNoEvents)
+    : mParent(aParent),
+      mStartIdx(UINT32_MAX),
+      mStateFlagsCopy(mParent->mStateFlags),
+      mQueueEvents(!aNoEvents) {
+#ifdef DEBUG
+  mIsDone = false;
+#endif
+
+#ifdef A11Y_LOG
+  if (mQueueEvents && logging::IsEnabled(logging::eEventTree)) {
+    logging::MsgBegin("EVENTS_TREE", "reordering tree before");
+    logging::AccessibleInfo("reordering for", mParent);
+    Controller()->RootEventTree().Log();
+    logging::MsgEnd();
+
+    if (logging::IsEnabled(logging::eVerbose)) {
+      logging::Tree("EVENTS_TREE", "Container tree", mParent->Document(),
+                    PrefixLog, static_cast<void*>(this));
+    }
+  }
+#endif
+
+  mParent->mStateFlags |= Accessible::eKidsMutating;
+}
+
+TreeMutation::~TreeMutation() {
+  MOZ_ASSERT(mIsDone, "Done() must be called explicitly");
+}
+
+void TreeMutation::AfterInsertion(Accessible* aChild) {
+  MOZ_ASSERT(aChild->Parent() == mParent);
+
+  if (static_cast<uint32_t>(aChild->mIndexInParent) < mStartIdx) {
+    mStartIdx = aChild->mIndexInParent + 1;
+  }
+
+  if (!mQueueEvents) {
+    return;
+  }
+
+  RefPtr<AccShowEvent> ev = new AccShowEvent(aChild);
+  DebugOnly<bool> added = Controller()->QueueMutationEvent(ev);
+  MOZ_ASSERT(added);
+  aChild->SetShowEventTarget(true);
+}
+
+void TreeMutation::BeforeRemoval(Accessible* aChild, bool aNoShutdown) {
+  MOZ_ASSERT(aChild->Parent() == mParent);
+
+  if (static_cast<uint32_t>(aChild->mIndexInParent) < mStartIdx) {
+    mStartIdx = aChild->mIndexInParent;
+  }
+
+  if (!mQueueEvents) {
+    return;
+  }
+
+  RefPtr<AccHideEvent> ev = new AccHideEvent(aChild, !aNoShutdown);
+  if (Controller()->QueueMutationEvent(ev)) {
+    aChild->SetHideEventTarget(true);
+  }
+}
+
+void TreeMutation::Done() {
+  MOZ_ASSERT(mParent->mStateFlags & Accessible::eKidsMutating);
+  mParent->mStateFlags &= ~Accessible::eKidsMutating;
+
+  uint32_t length = mParent->mChildren.Length();
+#ifdef DEBUG
+  for (uint32_t idx = 0; idx < mStartIdx && idx < length; idx++) {
+    MOZ_ASSERT(
+        mParent->mChildren[idx]->mIndexInParent == static_cast<int32_t>(idx),
+        "Wrong index detected");
+  }
+#endif
+
+  for (uint32_t idx = mStartIdx; idx < length; idx++) {
+    mParent->mChildren[idx]->mInt.mIndexOfEmbeddedChild = -1;
+  }
+
+  for (uint32_t idx = 0; idx < length; idx++) {
+    mParent->mChildren[idx]->mStateFlags |= Accessible::eGroupInfoDirty;
+  }
+
+  mParent->mEmbeddedObjCollector = nullptr;
+  mParent->mStateFlags |= mStateFlagsCopy & Accessible::eKidsMutating;
+
+#ifdef DEBUG
+  mIsDone = true;
+#endif
+
+#ifdef A11Y_LOG
+  if (mQueueEvents && logging::IsEnabled(logging::eEventTree)) {
+    logging::MsgBegin("EVENTS_TREE", "reordering tree after");
+    logging::AccessibleInfo("reordering for", mParent);
+    Controller()->RootEventTree().Log();
+    logging::MsgEnd();
+  }
+#endif
+}
+
+#ifdef A11Y_LOG
+const char* TreeMutation::PrefixLog(void* aData, Accessible* aAcc) {
+  TreeMutation* thisObj = reinterpret_cast<TreeMutation*>(aData);
+  if (thisObj->mParent == aAcc) {
+    return "_X_";
+  }
+  const EventTree& ret = thisObj->Controller()->RootEventTree();
+  if (ret.Find(aAcc)) {
+    return "_с_";
+  }
+  return "";
+}
+#endif
+
+////////////////////////////////////////////////////////////////////////////////
+// EventTree
+
+void EventTree::Shown(Accessible* aChild) {
+  RefPtr<AccShowEvent> ev = new AccShowEvent(aChild);
+  Controller(aChild)->WithdrawPrecedingEvents(&ev->mPrecedingEvents);
+  Mutated(ev);
+}
+
+void EventTree::Hidden(Accessible* aChild, bool aNeedsShutdown) {
+  RefPtr<AccHideEvent> ev = new AccHideEvent(aChild, aNeedsShutdown);
+  if (!aNeedsShutdown) {
+    Controller(aChild)->StorePrecedingEvent(ev);
+  }
+  Mutated(ev);
+}
+
+void EventTree::Process(const RefPtr<DocAccessible>& aDeathGrip) {
+  while (mFirst) {
+    // Skip a node and its subtree if its container is not in the document.
+    if (mFirst->mContainer->IsInDocument()) {
+      mFirst->Process(aDeathGrip);
+      if (aDeathGrip->IsDefunct()) {
+        return;
+      }
+    }
+    mFirst = std::move(mFirst->mNext);
+  }
+
+  MOZ_ASSERT(mContainer || mDependentEvents.IsEmpty(),
+             "No container, no events");
+  MOZ_ASSERT(!mContainer || !mContainer->IsDefunct(),
+             "Processing events for defunct container");
+  MOZ_ASSERT(!mFireReorder || mContainer, "No target for reorder event");
+
+  // Fire mutation events.
+  uint32_t eventsCount = mDependentEvents.Length();
+  for (uint32_t jdx = 0; jdx < eventsCount; jdx++) {
+    AccMutationEvent* mtEvent = mDependentEvents[jdx];
+    MOZ_ASSERT(mtEvent->Document(), "No document for event target");
+
+    // Fire all hide events that has to be fired before this show event.
+    if (mtEvent->IsShow()) {
+      AccShowEvent* showEv = downcast_accEvent(mtEvent);
+      for (uint32_t i = 0; i < showEv->mPrecedingEvents.Length(); i++) {
+        nsEventShell::FireEvent(showEv->mPrecedingEvents[i]);
+        if (aDeathGrip->IsDefunct()) {
+          return;
+        }
+      }
+    }
+
+    nsEventShell::FireEvent(mtEvent);
+    if (aDeathGrip->IsDefunct()) {
+      return;
+    }
+
+    if (mtEvent->mTextChangeEvent) {
+      nsEventShell::FireEvent(mtEvent->mTextChangeEvent);
+      if (aDeathGrip->IsDefunct()) {
+        return;
+      }
+    }
+
+    if (mtEvent->IsHide()) {
+      // Fire menupopup end event before a hide event if a menu goes away.
+
+      // XXX: We don't look into children of hidden subtree to find hiding
+      // menupopup (as we did prior bug 570275) because we don't do that when
+      // menu is showing (and that's impossible until bug 606924 is fixed).
+      // Nevertheless we should do this at least because layout coalesces
+      // the changes before our processing and we may miss some menupopup
+      // events. Now we just want to be consistent in content insertion/removal
+      // handling.
+      if (mtEvent->mAccessible->ARIARole() == roles::MENUPOPUP) {
+        nsEventShell::FireEvent(nsIAccessibleEvent::EVENT_MENUPOPUP_END,
+                                mtEvent->mAccessible);
+        if (aDeathGrip->IsDefunct()) {
+          return;
+        }
+      }
+
+      AccHideEvent* hideEvent = downcast_accEvent(mtEvent);
+      if (hideEvent->NeedsShutdown()) {
+        aDeathGrip->ShutdownChildrenInSubtree(mtEvent->mAccessible);
+      }
+    }
+  }
+
+  // Fire reorder event at last.
+  if (mFireReorder) {
+    nsEventShell::FireEvent(nsIAccessibleEvent::EVENT_REORDER, mContainer);
+    mContainer->Document()->MaybeNotifyOfValueChange(mContainer);
+  }
+
+  mDependentEvents.Clear();
+}
+
+EventTree* EventTree::FindOrInsert(Accessible* aContainer) {
+  if (!mFirst) {
+    mFirst.reset(new EventTree(aContainer, mDependentEvents.IsEmpty()));
+    return mFirst.get();
+  }
+
+  EventTree* prevNode = nullptr;
+  EventTree* node = mFirst.get();
+  do {
+    MOZ_ASSERT(!node->mContainer->IsApplication(),
+               "No event for application accessible is expected here");
+    MOZ_ASSERT(!node->mContainer->IsDefunct(),
+               "An event target has to be alive");
+
+    // Case of same target.
+    if (node->mContainer == aContainer) {
+      return node;
+    }
+
+    // Check if the given container is contained by a current node
+    Accessible* top = mContainer ? mContainer : aContainer->Document();
+    Accessible* parent = aContainer;
+    while (parent) {
+      // Reached a top, no match for a current event.
+      if (parent == top) {
+        break;
+      }
+
+      // We got a match.
+      if (parent->Parent() == node->mContainer) {
+        // Reject the node if it's contained by a show/hide event target
+        uint32_t evCount = node->mDependentEvents.Length();
+        for (uint32_t idx = 0; idx < evCount; idx++) {
+          AccMutationEvent* ev = node->mDependentEvents[idx];
+          if (ev->GetAccessible() == parent) {
+#ifdef A11Y_LOG
+            if (logging::IsEnabled(logging::eEventTree)) {
+              logging::MsgBegin("EVENTS_TREE",
+                                "Rejecting node contained by show/hide");
+              logging::AccessibleInfo("Node", aContainer);
+              logging::MsgEnd();
+            }
+#endif
+            // If the node is rejected, then check if it has related hide event
+            // on stack, and if so, then connect it to the parent show event.
+            if (ev->IsShow()) {
+              AccShowEvent* showEv = downcast_accEvent(ev);
+              Controller(aContainer)
+                  ->WithdrawPrecedingEvents(&showEv->mPrecedingEvents);
+            }
+            return nullptr;
+          }
+        }
+
+        return node->FindOrInsert(aContainer);
+      }
+
+      parent = parent->Parent();
+      MOZ_ASSERT(parent, "Wrong tree");
+    }
+
+    // If the given container contains a current node
+    // then
+    //   if show or hide of the given node contains a grand parent of the
+    //   current node then ignore the current node and its show and hide events
+    //   otherwise ignore the current node, but not its show and hide events
+    Accessible* curParent = node->mContainer;
+    while (curParent && !curParent->IsDoc()) {
+      if (curParent->Parent() != aContainer) {
+        curParent = curParent->Parent();
+        continue;
+      }
+
+      // Insert the tail node into the hierarchy between the current node and
+      // its parent.
+      node->mFireReorder = false;
+      UniquePtr<EventTree>& nodeOwnerRef = prevNode ? prevNode->mNext : mFirst;
+      UniquePtr<EventTree> newNode(
+          new EventTree(aContainer, mDependentEvents.IsEmpty()));
+      newNode->mFirst = std::move(nodeOwnerRef);
+      nodeOwnerRef = std::move(newNode);
+      nodeOwnerRef->mNext = std::move(node->mNext);
+
+      // Check if a next node is contained by the given node too, and move them
+      // under the given node if so.
+      prevNode = nodeOwnerRef.get();
+      node = nodeOwnerRef->mNext.get();
+      UniquePtr<EventTree>* nodeRef = &nodeOwnerRef->mNext;
+      EventTree* insNode = nodeOwnerRef->mFirst.get();
+      while (node) {
+        Accessible* curParent = node->mContainer;
+        while (curParent && !curParent->IsDoc()) {
+          if (curParent->Parent() != aContainer) {
+            curParent = curParent->Parent();
+            continue;
+          }
+
+          MOZ_ASSERT(!insNode->mNext);
+
+          node->mFireReorder = false;
+          insNode->mNext = std::move(*nodeRef);
+          insNode = insNode->mNext.get();
+
+          prevNode->mNext = std::move(node->mNext);
+          node = prevNode;
+          break;
+        }
+
+        prevNode = node;
+        nodeRef = &node->mNext;
+        node = node->mNext.get();
+      }
+
+      return nodeOwnerRef.get();
+    }
+
+    prevNode = node;
+  } while ((node = node->mNext.get()));
+
+  MOZ_ASSERT(prevNode, "Nowhere to insert");
+  MOZ_ASSERT(!prevNode->mNext, "Taken by another node");
+
+  // If 'this' node contains the given container accessible, then
+  //   do not emit a reorder event for the container
+  //   if a dependent show event target contains the given container then do not
+  //   emit show / hide events (see Process() method)
+
+  prevNode->mNext.reset(new EventTree(aContainer, mDependentEvents.IsEmpty()));
+  return prevNode->mNext.get();
+}
+
+void EventTree::Clear() {
+  mFirst = nullptr;
+  mNext = nullptr;
+  mContainer = nullptr;
+
+  uint32_t eventsCount = mDependentEvents.Length();
+  for (uint32_t jdx = 0; jdx < eventsCount; jdx++) {
+    mDependentEvents[jdx]->mEventType = AccEvent::eDoNotEmit;
+    AccHideEvent* ev = downcast_accEvent(mDependentEvents[jdx]);
+    if (ev && ev->NeedsShutdown()) {
+      ev->Document()->ShutdownChildrenInSubtree(ev->mAccessible);
+    }
+  }
+  mDependentEvents.Clear();
+}
+
+const EventTree* EventTree::Find(const Accessible* aContainer) const {
+  const EventTree* et = this;
+  while (et) {
+    if (et->mContainer == aContainer) {
+      return et;
+    }
+
+    if (et->mFirst) {
+      et = et->mFirst.get();
+      const EventTree* cet = et->Find(aContainer);
+      if (cet) {
+        return cet;
+      }
+    }
+
+    et = et->mNext.get();
+    const EventTree* cet = et->Find(aContainer);
+    if (cet) {
+      return cet;
+    }
+  }
+
+  return nullptr;
+}
+
+#ifdef A11Y_LOG
+void EventTree::Log(uint32_t aLevel) const {
+  if (aLevel == UINT32_MAX) {
+    if (mFirst) {
+      mFirst->Log(0);
+    }
+    return;
+  }
+
+  for (uint32_t i = 0; i < aLevel; i++) {
+    printf("  ");
+  }
+  logging::AccessibleInfo("container", mContainer);
+
+  for (uint32_t i = 0; i < mDependentEvents.Length(); i++) {
+    AccMutationEvent* ev = mDependentEvents[i];
+    if (ev->IsShow()) {
+      for (uint32_t i = 0; i < aLevel + 1; i++) {
+        printf("  ");
+      }
+      logging::AccessibleInfo("shown", ev->mAccessible);
+
+      AccShowEvent* showEv = downcast_accEvent(ev);
+      for (uint32_t i = 0; i < showEv->mPrecedingEvents.Length(); i++) {
+        for (uint32_t j = 0; j < aLevel + 1; j++) {
+          printf("  ");
+        }
+        logging::AccessibleInfo("preceding",
+                                showEv->mPrecedingEvents[i]->mAccessible);
+      }
+    } else {
+      for (uint32_t i = 0; i < aLevel + 1; i++) {
+        printf("  ");
+      }
+      logging::AccessibleInfo("hidden", ev->mAccessible);
+    }
+  }
+
+  if (mFirst) {
+    mFirst->Log(aLevel + 1);
+  }
+
+  if (mNext) {
+    mNext->Log(aLevel);
+  }
+}
+#endif
+
+void EventTree::Mutated(AccMutationEvent* aEv) {
+  // If shown or hidden node is a root of previously mutated subtree, then
+  // discard those subtree mutations as we are no longer interested in them.
+  UniquePtr<EventTree>* node = &mFirst;
+  while (*node) {
+    Accessible* cntr = (*node)->mContainer;
+    while (cntr != mContainer) {
+      if (cntr == aEv->mAccessible) {
+#ifdef A11Y_LOG
+        if (logging::IsEnabled(logging::eEventTree)) {
+          logging::MsgBegin("EVENTS_TREE", "Trim subtree");
+          logging::AccessibleInfo("Show/hide container", aEv->mAccessible);
+          logging::AccessibleInfo("Trimmed subtree root", (*node)->mContainer);
+          logging::MsgEnd();
+        }
+#endif
+
+        // If the new hide is part of a move and it contains existing child
+        // shows, then move preceding events from the child shows to the buffer,
+        // so the ongoing show event will pick them up.
+        if (aEv->IsHide()) {
+          AccHideEvent* hideEv = downcast_accEvent(aEv);
+          if (!hideEv->mNeedsShutdown) {
+            for (uint32_t i = 0; i < (*node)->mDependentEvents.Length(); i++) {
+              AccMutationEvent* childEv = (*node)->mDependentEvents[i];
+              if (childEv->IsShow()) {
+                AccShowEvent* childShowEv = downcast_accEvent(childEv);
+                if (childShowEv->mPrecedingEvents.Length() > 0) {
+                  Controller(mContainer)
+                      ->StorePrecedingEvents(
+                          std::move(childShowEv->mPrecedingEvents));
+                }
+              }
+            }
+          }
+        }
+        // If the new show contains existing child shows, then move preceding
+        // events from the child shows to the new show.
+        else if (aEv->IsShow()) {
+          AccShowEvent* showEv = downcast_accEvent(aEv);
+          for (uint32_t i = 0; (*node)->mDependentEvents.Length(); i++) {
+            AccMutationEvent* childEv = (*node)->mDependentEvents[i];
+            if (childEv->IsShow()) {
+              AccShowEvent* showChildEv = downcast_accEvent(childEv);
+              if (showChildEv->mPrecedingEvents.Length() > 0) {
+#ifdef A11Y_LOG
+                if (logging::IsEnabled(logging::eEventTree)) {
+                  logging::MsgBegin("EVENTS_TREE", "Adopt preceding events");
+                  logging::AccessibleInfo("Parent", aEv->mAccessible);
+                  for (uint32_t j = 0;
+                       j < showChildEv->mPrecedingEvents.Length(); j++) {
+                    logging::AccessibleInfo(
+                        "Adoptee",
+                        showChildEv->mPrecedingEvents[i]->mAccessible);
+                  }
+                  logging::MsgEnd();
+                }
+#endif
+                showEv->mPrecedingEvents.AppendElements(
+                    showChildEv->mPrecedingEvents);
+              }
+            }
+          }
+        }
+
+        *node = std::move((*node)->mNext);
+        break;
+      }
+      cntr = cntr->Parent();
+    }
+    if (cntr == aEv->mAccessible) {
+      continue;
+    }
+    node = &(*node)->mNext;
+  }
+
+  AccMutationEvent* prevEvent = mDependentEvents.SafeLastElement(nullptr);
+  mDependentEvents.AppendElement(aEv);
+
+  // Coalesce text change events from this hide/show event and the previous one.
+  if (prevEvent && aEv->mEventType == prevEvent->mEventType) {
+    if (aEv->IsHide()) {
+      // XXX: we need a way to ignore SplitNode and JoinNode() when they do not
+      // affect the text within the hypertext.
+      AccTextChangeEvent* prevTextEvent = prevEvent->mTextChangeEvent;
+      if (prevTextEvent) {
+        AccHideEvent* hideEvent = downcast_accEvent(aEv);
+        AccHideEvent* prevHideEvent = downcast_accEvent(prevEvent);
+
+        if (prevHideEvent->mNextSibling == hideEvent->mAccessible) {
+          hideEvent->mAccessible->AppendTextTo(prevTextEvent->mModifiedText);
+        } else if (prevHideEvent->mPrevSibling == hideEvent->mAccessible) {
+          uint32_t oldLen = prevTextEvent->GetLength();
+          hideEvent->mAccessible->AppendTextTo(prevTextEvent->mModifiedText);
+          prevTextEvent->mStart -= prevTextEvent->GetLength() - oldLen;
+        }
+
+        hideEvent->mTextChangeEvent.swap(prevEvent->mTextChangeEvent);
+      }
+    } else {
+      AccTextChangeEvent* prevTextEvent = prevEvent->mTextChangeEvent;
+      if (prevTextEvent) {
+        if (aEv->mAccessible->IndexInParent() ==
+            prevEvent->mAccessible->IndexInParent() + 1) {
+          // If tail target was inserted after this target, i.e. tail target is
+          // next sibling of this target.
+          aEv->mAccessible->AppendTextTo(prevTextEvent->mModifiedText);
+        } else if (aEv->mAccessible->IndexInParent() ==
+                   prevEvent->mAccessible->IndexInParent() - 1) {
+          // If tail target was inserted before this target, i.e. tail target is
+          // previous sibling of this target.
+          nsAutoString startText;
+          aEv->mAccessible->AppendTextTo(startText);
+          prevTextEvent->mModifiedText =
+              startText + prevTextEvent->mModifiedText;
+          prevTextEvent->mStart -= startText.Length();
+        }
+
+        aEv->mTextChangeEvent.swap(prevEvent->mTextChangeEvent);
+      }
+    }
+  }
+
+  // Create a text change event caused by this hide/show event. When a node is
+  // hidden/removed or shown/appended, the text in an ancestor hyper text will
+  // lose or get new characters.
+  if (aEv->mTextChangeEvent || !mContainer->IsHyperText()) {
+    return;
+  }
+
+  nsAutoString text;
+  aEv->mAccessible->AppendTextTo(text);
+  if (text.IsEmpty()) {
+    return;
+  }
+
+  int32_t offset = mContainer->AsHyperText()->GetChildOffset(aEv->mAccessible);
+  aEv->mTextChangeEvent = new AccTextChangeEvent(
+      mContainer, offset, text, aEv->IsShow(),
+      aEv->mIsFromUserInput ? eFromUserInput : eNoUserInput);
+}