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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "DepthOrderedFrameList.h"
#include "nsContainerFrame.h"
#include "nsIFrame.h"
namespace mozilla {
void DepthOrderedFrameList::Add(nsIFrame* aFrame) {
MOZ_ASSERT(aFrame);
if (auto p = mFrames.lookupForAdd(aFrame)) {
// We don't expect the depth of a frame in the list to change.
MOZ_ASSERT(p->value() == aFrame->GetDepthInFrameTree());
} else {
if (!mFrames.add(p, aFrame, aFrame->GetDepthInFrameTree())) {
NS_WARNING("failed to add frame to DepthOrderedFrameList");
}
if (mFrames.count() == 1) {
// We just added the first frame, so can directly set up mSortedFrames.
// (Lists that only contain a single frame are common.)
MOZ_ASSERT(mSortedFrames.IsEmpty());
mSortedFrames.AppendElement(FrameAndDepth{aFrame, p->value()});
} else {
// Clear mSortedFrames, so that we'll rebuild it when needed.
mSortedFrames.ClearAndRetainStorage();
}
}
}
nsIFrame* DepthOrderedFrameList::PopShallowestRoot() {
MOZ_ASSERT(!mFrames.empty(), "no frames in list!");
EnsureSortedList();
// List is sorted in order of decreasing depth, so there are no shallower
// frames than the last one.
const FrameAndDepth& lastFAD = mSortedFrames.PopLastElement();
nsIFrame* frame = lastFAD.mFrame;
// We don't expect frame to change depths.
MOZ_ASSERT(frame->GetDepthInFrameTree() == lastFAD.mDepth);
// Keep the hashtable in sync with the sorted list.
mFrames.remove(frame);
return frame;
}
bool DepthOrderedFrameList::FrameIsAncestorOfAnyElement(
nsIFrame* aFrame) const {
MOZ_ASSERT(aFrame);
// Look for a path from any element to aFrame, following GetParent(). This
// check mirrors what FrameNeedsReflow() would have done if the reflow root
// didn't get in the way.
for (auto iter = mFrames.iter(); !iter.done(); iter.next()) {
nsIFrame* f = iter.get().key();
do {
if (f == aFrame) {
return true;
}
f = f->GetParent();
} while (f);
}
return false;
}
void DepthOrderedFrameList::BuildSortedList() const {
MOZ_ASSERT(mSortedFrames.IsEmpty());
mSortedFrames.SetCapacity(mFrames.count());
for (auto iter = mFrames.iter(); !iter.done(); iter.next()) {
mSortedFrames.AppendElement(
FrameAndDepth{iter.get().key(), iter.get().value()});
}
mSortedFrames.Sort();
}
} // namespace mozilla