C++ nsHTMLReflowState::AvailableISize方法代码示例

static nscoord
GetAvailableContentISize(const nsHTMLReflowState& aReflowState)
{
    if (aReflowState.AvailableISize() == NS_INTRINSICSIZE) {
        return NS_INTRINSICSIZE;
    }

    WritingMode wm = aReflowState.GetWritingMode();
    nscoord borderPaddingISize =
        aReflowState.ComputedLogicalBorderPadding().IStartEnd(wm);
    return std::max(0, aReflowState.AvailableISize() - borderPaddingISize);
}

/* virtual */ void
nsRubyTextFrame::Reflow(nsPresContext* aPresContext,
                        nsHTMLReflowMetrics& aDesiredSize,
                        const nsHTMLReflowState& aReflowState,
                        nsReflowStatus& aStatus)
{
  DO_GLOBAL_REFLOW_COUNT("nsRubyBaseFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  
  if (!aReflowState.mLineLayout) {
    NS_ASSERTION(aReflowState.mLineLayout,
                 "No line layout provided to RubyTextFrame reflow method.");
    aStatus = NS_FRAME_COMPLETE;
    return;
  }

  WritingMode lineWM = aReflowState.mLineLayout->GetWritingMode();
  WritingMode frameWM = aReflowState.GetWritingMode();
  LogicalMargin borderPadding = aReflowState.ComputedLogicalBorderPadding();
  aStatus = NS_FRAME_COMPLETE;
  LogicalSize availSize(lineWM, aReflowState.AvailableWidth(),
                        aReflowState.AvailableHeight());

  // Begin the span for the ruby text frame
  nscoord availableISize = aReflowState.AvailableISize();
  NS_ASSERTION(availableISize != NS_UNCONSTRAINEDSIZE,
               "should no longer use available widths");
  // Subtract off inline axis border+padding from availableISize
  availableISize -= borderPadding.IStartEnd(frameWM);
  aReflowState.mLineLayout->BeginSpan(this, &aReflowState,
                                      borderPadding.IStart(frameWM),
                                      availableISize, &mBaseline);

  for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
    nsReflowStatus frameReflowStatus;
    nsHTMLReflowMetrics metrics(aReflowState, aDesiredSize.mFlags);

    bool pushedFrame;
    aReflowState.mLineLayout->ReflowFrame(e.get(), frameReflowStatus,
                                          &metrics, pushedFrame);
    NS_ASSERTION(!pushedFrame,
                 "Ruby line breaking is not yet implemented");
    e.get()->SetSize(LogicalSize(lineWM, metrics.ISize(lineWM),
                                 metrics.BSize(lineWM)));
  }

  aDesiredSize.ISize(lineWM) = aReflowState.mLineLayout->EndSpan(this);
  nsLayoutUtils::SetBSizeFromFontMetrics(this, aDesiredSize, aReflowState,
                                         borderPadding, lineWM, frameWM);

}

void
nsTableCellFrame::Reflow(nsPresContext*           aPresContext,
                         nsHTMLReflowMetrics&     aDesiredSize,
                         const nsHTMLReflowState& aReflowState,
                         nsReflowStatus&          aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsTableCellFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);

  if (aReflowState.mFlags.mSpecialBSizeReflow) {
    FirstInFlow()->AddStateBits(NS_TABLE_CELL_HAD_SPECIAL_REFLOW);
  }

  // see if a special bsize reflow needs to occur due to having a pct height
  nsTableFrame::CheckRequestSpecialBSizeReflow(aReflowState);

  aStatus = NS_FRAME_COMPLETE;
  WritingMode wm = aReflowState.GetWritingMode();
  LogicalSize availSize(wm, aReflowState.AvailableISize(),
                            aReflowState.AvailableBSize());

  LogicalMargin borderPadding = aReflowState.ComputedLogicalPadding();
  LogicalMargin border = GetBorderWidth(wm);
  borderPadding += border;

  // reduce available space by insets, if we're in a constrained situation
  availSize.ISize(wm) -= borderPadding.IStartEnd(wm);
  if (NS_UNCONSTRAINEDSIZE != availSize.BSize(wm)) {
    availSize.BSize(wm) -= borderPadding.BStartEnd(wm);
  }

  // Try to reflow the child into the available space. It might not
  // fit or might need continuing.
  if (availSize.BSize(wm) < 0) {
    availSize.BSize(wm) = 1;
  }

  nsHTMLReflowMetrics kidSize(wm, aDesiredSize.mFlags);
  kidSize.ClearSize();
  SetPriorAvailISize(aReflowState.AvailableISize());
  nsIFrame* firstKid = mFrames.FirstChild();
  NS_ASSERTION(firstKid, "Frame construction error, a table cell always has an inner cell frame");
  nsTableFrame* tableFrame = GetTableFrame();

  if (aReflowState.mFlags.mSpecialBSizeReflow) {
    const_cast<nsHTMLReflowState&>(aReflowState).
      SetComputedBSize(BSize(wm) - borderPadding.BStartEnd(wm));
    DISPLAY_REFLOW_CHANGE();
  }
  else if (aPresContext->IsPaginated()) {
    nscoord computedUnpaginatedBSize =
      CalcUnpaginatedBSize(aPresContext, (nsTableCellFrame&)*this,
                           *tableFrame, borderPadding.BStartEnd(wm));
    if (computedUnpaginatedBSize > 0) {
      const_cast<nsHTMLReflowState&>(aReflowState).SetComputedBSize(computedUnpaginatedBSize);
      DISPLAY_REFLOW_CHANGE();
    }
  }
  else {
    SetHasPctOverBSize(false);
  }

  WritingMode kidWM = firstKid->GetWritingMode();
  nsHTMLReflowState kidReflowState(aPresContext, aReflowState, firstKid,
                                   availSize.ConvertTo(kidWM, wm));

  // Don't be a percent height observer if we're in the middle of
  // special-bsize reflow, in case we get an accidental NotifyPercentBSize()
  // call (which we shouldn't honor during special-bsize reflow)
  if (!aReflowState.mFlags.mSpecialBSizeReflow) {
    // mPercentBSizeObserver is for children of cells in quirks mode,
    // but only those than are tables in standards mode.  NeedsToObserve
    // will determine how far this is propagated to descendants.
    kidReflowState.mPercentBSizeObserver = this;
  }
  // Don't propagate special bsize reflow state to our kids
  kidReflowState.mFlags.mSpecialBSizeReflow = false;

  if (aReflowState.mFlags.mSpecialBSizeReflow ||
      FirstInFlow()->HasAnyStateBits(NS_TABLE_CELL_HAD_SPECIAL_REFLOW)) {
    // We need to force the kid to have mBResize set if we've had a
    // special reflow in the past, since the non-special reflow needs to
    // resize back to what it was without the special bsize reflow.
    kidReflowState.SetBResize(true);
  }

  nsSize containerSize =
    aReflowState.ComputedSizeAsContainerIfConstrained();

  LogicalPoint kidOrigin(wm, borderPadding.IStart(wm),
                         borderPadding.BStart(wm));
  nsRect origRect = firstKid->GetRect();
  nsRect origVisualOverflow = firstKid->GetVisualOverflowRect();
  bool firstReflow = firstKid->HasAnyStateBits(NS_FRAME_FIRST_REFLOW);

  ReflowChild(firstKid, aPresContext, kidSize, kidReflowState,
              wm, kidOrigin, containerSize, 0, aStatus);
  if (NS_FRAME_OVERFLOW_IS_INCOMPLETE(aStatus)) {
    // Don't pass OVERFLOW_INCOMPLETE through tables until they can actually handle it
//.........这里部分代码省略.........

/* virtual */ void
nsRubyBaseContainerFrame::Reflow(nsPresContext* aPresContext,
                                 nsHTMLReflowMetrics& aDesiredSize,
                                 const nsHTMLReflowState& aReflowState,
                                 nsReflowStatus& aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsRubyBaseContainerFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  aStatus = NS_FRAME_COMPLETE;

  if (!aReflowState.mLineLayout) {
    NS_ASSERTION(
      aReflowState.mLineLayout,
      "No line layout provided to RubyBaseContainerFrame reflow method.");
    return;
  }

  MoveOverflowToChildList();
  // Ask text containers to drain overflows
  AutoRubyTextContainerArray textContainers(this);
  const uint32_t rtcCount = textContainers.Length();
  for (uint32_t i = 0; i < rtcCount; i++) {
    textContainers[i]->MoveOverflowToChildList();
  }

  WritingMode lineWM = aReflowState.mLineLayout->GetWritingMode();
  LogicalSize availSize(lineWM, aReflowState.AvailableISize(),
                        aReflowState.AvailableBSize());

  // We have a reflow state and a line layout for each RTC.
  // They are conceptually the state of the RTCs, but we don't actually
  // reflow those RTCs in this code. These two arrays are holders of
  // the reflow states and line layouts.
  // Since there are pointers refer to reflow states and line layouts,
  // it is necessary to guarantee that they won't be moved. For this
  // reason, they are wrapped in UniquePtr here.
  nsAutoTArray<UniquePtr<nsHTMLReflowState>, RTC_ARRAY_SIZE> reflowStates;
  nsAutoTArray<UniquePtr<nsLineLayout>, RTC_ARRAY_SIZE> lineLayouts;
  reflowStates.SetCapacity(rtcCount);
  lineLayouts.SetCapacity(rtcCount);

  // Begin the line layout for each ruby text container in advance.
  bool hasSpan = false;
  for (uint32_t i = 0; i < rtcCount; i++) {
    nsRubyTextContainerFrame* textContainer = textContainers[i];
    if (textContainer->IsSpanContainer()) {
      hasSpan = true;
    }

    nsHTMLReflowState* reflowState = new nsHTMLReflowState(
      aPresContext, *aReflowState.parentReflowState, textContainer,
      availSize.ConvertTo(textContainer->GetWritingMode(), lineWM));
    reflowStates.AppendElement(reflowState);
    nsLineLayout* lineLayout = new nsLineLayout(aPresContext,
                                                reflowState->mFloatManager,
                                                reflowState, nullptr,
                                                aReflowState.mLineLayout);
    lineLayout->SetSuppressLineWrap(true);
    lineLayouts.AppendElement(lineLayout);

    // Line number is useless for ruby text
    // XXX nullptr here may cause problem, see comments for
    //     nsLineLayout::mBlockRS and nsLineLayout::AddFloat
    lineLayout->Init(nullptr, reflowState->CalcLineHeight(), -1);
    reflowState->mLineLayout = lineLayout;

    // Border and padding are suppressed on ruby text containers.
    // If the writing mode is vertical-rl, the horizontal position of
    // rt frames will be updated when reflowing this text container,
    // hence leave container size 0 here for now.
    lineLayout->BeginLineReflow(0, 0, reflowState->ComputedISize(),
                                NS_UNCONSTRAINEDSIZE,
                                false, false, lineWM, nsSize(0, 0));
    lineLayout->AttachRootFrameToBaseLineLayout();
  }

  aReflowState.mLineLayout->BeginSpan(this, &aReflowState,
                                      0, aReflowState.AvailableISize(),
                                      &mBaseline);

  bool allowInitialLineBreak, allowLineBreak;
  GetIsLineBreakAllowed(this, aReflowState.mLineLayout->LineIsBreakable(),
                        &allowInitialLineBreak, &allowLineBreak);

  nscoord isize = 0;
  // Reflow columns excluding any span
  ReflowState reflowState = {
    allowInitialLineBreak, allowLineBreak && !hasSpan,
    textContainers, aReflowState, reflowStates
  };
  isize = ReflowColumns(reflowState, aStatus);
  DebugOnly<nscoord> lineSpanSize = aReflowState.mLineLayout->EndSpan(this);
  aDesiredSize.ISize(lineWM) = isize;
  // When there are no frames inside the ruby base container, EndSpan
  // will return 0. However, in this case, the actual width of the
  // container could be non-zero because of non-empty ruby annotations.
  // XXX When bug 765861 gets fixed, this warning should be upgraded.
  NS_WARN_IF_FALSE(NS_INLINE_IS_BREAK(aStatus) ||
                   isize == lineSpanSize || mFrames.IsEmpty(), "bad isize");
//.........这里部分代码省略.........

/* virtual */ void
nsRubyFrame::Reflow(nsPresContext* aPresContext,
                    nsHTMLReflowMetrics& aDesiredSize,
                    const nsHTMLReflowState& aReflowState,
                    nsReflowStatus& aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsRubyFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  
  if (!aReflowState.mLineLayout) {
    NS_ASSERTION(aReflowState.mLineLayout,
                 "No line layout provided to RubyFrame reflow method.");
    aStatus = NS_FRAME_COMPLETE;
    return;
  }

  // Grab overflow frames from prev-in-flow and its own.
  MoveOverflowToChildList();

  // Clear leadings
  mBStartLeading = mBEndLeading = 0;

  // Begin the span for the ruby frame
  WritingMode frameWM = aReflowState.GetWritingMode();
  WritingMode lineWM = aReflowState.mLineLayout->GetWritingMode();
  LogicalMargin borderPadding = aReflowState.ComputedLogicalBorderPadding();
  nscoord startEdge = 0;
  const bool boxDecorationBreakClone =
    StyleBorder()->mBoxDecorationBreak == NS_STYLE_BOX_DECORATION_BREAK_CLONE;
  if (boxDecorationBreakClone || !GetPrevContinuation()) {
    startEdge = borderPadding.IStart(frameWM);
  }
  NS_ASSERTION(aReflowState.AvailableISize() != NS_UNCONSTRAINEDSIZE,
               "should no longer use available widths");
  nscoord availableISize = aReflowState.AvailableISize();
  availableISize -= startEdge + borderPadding.IEnd(frameWM);
  aReflowState.mLineLayout->BeginSpan(this, &aReflowState,
                                      startEdge, availableISize, &mBaseline);

  aStatus = NS_FRAME_COMPLETE;
  for (RubySegmentEnumerator e(this); !e.AtEnd(); e.Next()) {
    ReflowSegment(aPresContext, aReflowState, e.GetBaseContainer(), aStatus);

    if (NS_INLINE_IS_BREAK(aStatus)) {
      // A break occurs when reflowing the segment.
      // Don't continue reflowing more segments.
      break;
    }
  }

  ContinuationTraversingState pullState(this);
  while (aStatus == NS_FRAME_COMPLETE) {
    nsRubyBaseContainerFrame* baseContainer =
      PullOneSegment(aReflowState.mLineLayout, pullState);
    if (!baseContainer) {
      // No more continuations after, finish now.
      break;
    }
    ReflowSegment(aPresContext, aReflowState, baseContainer, aStatus);
  }
  // We never handle overflow in ruby.
  MOZ_ASSERT(!NS_FRAME_OVERFLOW_IS_INCOMPLETE(aStatus));

  aDesiredSize.ISize(lineWM) = aReflowState.mLineLayout->EndSpan(this);
  if (boxDecorationBreakClone || !GetPrevContinuation()) {
    aDesiredSize.ISize(lineWM) += borderPadding.IStart(frameWM);
  }
  if (boxDecorationBreakClone || NS_FRAME_IS_COMPLETE(aStatus)) {
    aDesiredSize.ISize(lineWM) += borderPadding.IEnd(frameWM);
  }

  nsLayoutUtils::SetBSizeFromFontMetrics(this, aDesiredSize,
                                         borderPadding, lineWM, frameWM);
}

void
nsRubyFrame::ReflowSegment(nsPresContext* aPresContext,
                           const nsHTMLReflowState& aReflowState,
                           nsRubyBaseContainerFrame* aBaseContainer,
                           nsReflowStatus& aStatus)
{
  WritingMode lineWM = aReflowState.mLineLayout->GetWritingMode();
  LogicalSize availSize(lineWM, aReflowState.AvailableISize(),
                        aReflowState.AvailableBSize());
  WritingMode rubyWM = GetWritingMode();
  NS_ASSERTION(!rubyWM.IsOrthogonalTo(lineWM),
               "Ruby frame writing-mode shouldn't be orthogonal to its line");

  AutoRubyTextContainerArray textContainers(aBaseContainer);
  const uint32_t rtcCount = textContainers.Length();

  nsHTMLReflowMetrics baseMetrics(aReflowState);
  bool pushedFrame;
  aReflowState.mLineLayout->ReflowFrame(aBaseContainer, aStatus,
                                        &baseMetrics, pushedFrame);

  if (NS_INLINE_IS_BREAK_BEFORE(aStatus)) {
    if (aBaseContainer != mFrames.FirstChild()) {
      // Some segments may have been reflowed before, hence it is not
      // a break-before for the ruby container.
      aStatus = NS_INLINE_LINE_BREAK_AFTER(NS_FRAME_NOT_COMPLETE);
      PushChildren(aBaseContainer, aBaseContainer->GetPrevSibling());
      aReflowState.mLineLayout->SetDirtyNextLine();
    }
    // This base container is not placed at all, we can skip all
    // text containers paired with it.
    return;
  }
  if (NS_FRAME_IS_NOT_COMPLETE(aStatus)) {
    // It always promise that if the status is incomplete, there is a
    // break occurs. Break before has been processed above. However,
    // it is possible that break after happens with the frame reflow
    // completed. It happens if there is a force break at the end.
    MOZ_ASSERT(NS_INLINE_IS_BREAK_AFTER(aStatus));
    // Find the previous sibling which we will
    // insert new continuations after.
    nsIFrame* lastChild;
    if (rtcCount > 0) {
      lastChild = textContainers.LastElement();
    } else {
      lastChild = aBaseContainer;
    }

    // Create continuations for the base container
    nsIFrame* newBaseContainer = CreateNextInFlow(aBaseContainer);
    // newBaseContainer is null if there are existing next-in-flows.
    // We only need to move and push if there were not.
    if (newBaseContainer) {
      // Move the new frame after all the text containers
      mFrames.RemoveFrame(newBaseContainer);
      mFrames.InsertFrame(nullptr, lastChild, newBaseContainer);

      // Create continuations for text containers
      nsIFrame* newLastChild = newBaseContainer;
      for (uint32_t i = 0; i < rtcCount; i++) {
        nsIFrame* newTextContainer = CreateNextInFlow(textContainers[i]);
        MOZ_ASSERT(newTextContainer, "Next-in-flow of rtc should not exist "
                   "if the corresponding rbc does not");
        mFrames.RemoveFrame(newTextContainer);
        mFrames.InsertFrame(nullptr, newLastChild, newTextContainer);
        newLastChild = newTextContainer;
      }
    }
    if (lastChild != mFrames.LastChild()) {
      // Always push the next frame after the last child in this segment.
      // It is possible that we pulled it back before our next-in-flow
      // drain our overflow.
      PushChildren(lastChild->GetNextSibling(), lastChild);
      aReflowState.mLineLayout->SetDirtyNextLine();
    }
  } else {
    // If the ruby base container is reflowed completely, the line
    // layout will remove the next-in-flows of that frame. But the
    // line layout is not aware of the ruby text containers, hence
    // it is necessary to remove them here.
    for (uint32_t i = 0; i < rtcCount; i++) {
      nsIFrame* nextRTC = textContainers[i]->GetNextInFlow();
      if (nextRTC) {
        nextRTC->GetParent()->DeleteNextInFlowChild(nextRTC, true);
      }
    }
  }

  nscoord segmentISize = baseMetrics.ISize(lineWM);
  const nsSize dummyContainerSize;
  LogicalRect baseRect =
    aBaseContainer->GetLogicalRect(lineWM, dummyContainerSize);
  // We need to position our rtc frames on one side or the other of the
  // base container's rect, using a coordinate space that's relative to
  // the ruby frame. Right now, the base container's rect's block-axis
  // position is relative to the block container frame containing the
  // lines, so we use 0 instead. (i.e. we assume that the base container
  // is adjacent to the ruby frame's block-start edge.)
  // XXX We may need to add border/padding here. See bug 1055667.
  baseRect.BStart(lineWM) = 0;
//.........这里部分代码省略.........

void
ViewportFrame::Reflow(nsPresContext*           aPresContext,
                      nsHTMLReflowMetrics&     aDesiredSize,
                      const nsHTMLReflowState& aReflowState,
                      nsReflowStatus&          aStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("ViewportFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
  NS_FRAME_TRACE_REFLOW_IN("ViewportFrame::Reflow");

  // Initialize OUT parameters
  aStatus = NS_FRAME_COMPLETE;

  // Because |Reflow| sets ComputedBSize() on the child to our
  // ComputedBSize().
  AddStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE);

  // Set our size up front, since some parts of reflow depend on it
  // being already set.  Note that the computed height may be
  // unconstrained; that's ok.  Consumers should watch out for that.
  SetSize(nsSize(aReflowState.ComputedWidth(), aReflowState.ComputedHeight()));

  // Reflow the main content first so that the placeholders of the
  // fixed-position frames will be in the right places on an initial
  // reflow.
  nscoord kidBSize = 0;
  WritingMode wm = aReflowState.GetWritingMode();

  if (mFrames.NotEmpty()) {
    // Deal with a non-incremental reflow or an incremental reflow
    // targeted at our one-and-only principal child frame.
    if (aReflowState.ShouldReflowAllKids() ||
        aReflowState.IsVResize() ||
        NS_SUBTREE_DIRTY(mFrames.FirstChild())) {
      // Reflow our one-and-only principal child frame
      nsIFrame*           kidFrame = mFrames.FirstChild();
      nsHTMLReflowMetrics kidDesiredSize(aReflowState);
      WritingMode         wm = kidFrame->GetWritingMode();
      LogicalSize         availableSpace = aReflowState.AvailableSize(wm);
      nsHTMLReflowState   kidReflowState(aPresContext, aReflowState,
                                         kidFrame, availableSpace);

      // Reflow the frame
      kidReflowState.SetComputedBSize(aReflowState.ComputedBSize());
      ReflowChild(kidFrame, aPresContext, kidDesiredSize, kidReflowState,
                  0, 0, 0, aStatus);
      kidBSize = kidDesiredSize.BSize(wm);

      FinishReflowChild(kidFrame, aPresContext, kidDesiredSize, nullptr, 0, 0, 0);
    } else {
      kidBSize = LogicalSize(wm, mFrames.FirstChild()->GetSize()).BSize(wm);
    }
  }

  NS_ASSERTION(aReflowState.AvailableISize() != NS_UNCONSTRAINEDSIZE,
               "shouldn't happen anymore");

  // Return the max size as our desired size
  LogicalSize maxSize(wm, aReflowState.AvailableISize(),
                      // Being flowed initially at an unconstrained block size
                      // means we should return our child's intrinsic size.
                      aReflowState.ComputedBSize() != NS_UNCONSTRAINEDSIZE
                        ? aReflowState.ComputedBSize()
                        : kidBSize);
  aDesiredSize.SetSize(wm, maxSize);
  aDesiredSize.SetOverflowAreasToDesiredBounds();

  if (HasAbsolutelyPositionedChildren()) {
    // Make a copy of the reflow state and change the computed width and height
    // to reflect the available space for the fixed items
    nsHTMLReflowState reflowState(aReflowState);

    if (reflowState.AvailableBSize() == NS_UNCONSTRAINEDSIZE) {
      // We have an intrinsic-height document with abs-pos/fixed-pos children.
      // Set the available height and mComputedHeight to our chosen height.
      reflowState.AvailableBSize() = maxSize.BSize(wm);
      // Not having border/padding simplifies things
      NS_ASSERTION(reflowState.ComputedPhysicalBorderPadding() == nsMargin(0,0,0,0),
                   "Viewports can't have border/padding");
      reflowState.SetComputedBSize(maxSize.BSize(wm));
    }

    nsRect rect = AdjustReflowStateAsContainingBlock(&reflowState);
    nsOverflowAreas* overflowAreas = &aDesiredSize.mOverflowAreas;
    nsIScrollableFrame* rootScrollFrame =
                    aPresContext->PresShell()->GetRootScrollFrameAsScrollable();
    if (rootScrollFrame && !rootScrollFrame->IsIgnoringViewportClipping()) {
      overflowAreas = nullptr;
    }
    AbsPosReflowFlags flags =
      AbsPosReflowFlags::eCBWidthAndHeightChanged; // XXX could be optimized
    GetAbsoluteContainingBlock()->Reflow(this, aPresContext, reflowState, aStatus,
                                         rect, flags, overflowAreas);
  }

  if (mFrames.NotEmpty()) {
    ConsiderChildOverflow(aDesiredSize.mOverflowAreas, mFrames.FirstChild());
  }

//.........这里部分代码省略.........

void
nsInlineFrame::ReflowFrames(nsPresContext* aPresContext,
                            const nsHTMLReflowState& aReflowState,
                            InlineReflowState& irs,
                            nsHTMLReflowMetrics& aMetrics,
                            nsReflowStatus& aStatus)
{
  aStatus = NS_FRAME_COMPLETE;

  nsLineLayout* lineLayout = aReflowState.mLineLayout;
  bool inFirstLine = aReflowState.mLineLayout->GetInFirstLine();
  RestyleManager* restyleManager = aPresContext->RestyleManager();
  WritingMode frameWM = aReflowState.GetWritingMode();
  WritingMode lineWM = aReflowState.mLineLayout->mRootSpan->mWritingMode;
  LogicalMargin framePadding = aReflowState.ComputedLogicalBorderPadding();
  nscoord startEdge = 0;
  const bool boxDecorationBreakClone =
    MOZ_UNLIKELY(StyleBorder()->mBoxDecorationBreak ==
                   NS_STYLE_BOX_DECORATION_BREAK_CLONE);
  // Don't offset by our start borderpadding if we have a prev continuation or
  // if we're in a part of an {ib} split other than the first one. For
  // box-decoration-break:clone we always offset our start since all
  // continuations have border/padding.
  if ((!GetPrevContinuation() && !FrameIsNonFirstInIBSplit()) ||
      boxDecorationBreakClone) {
    startEdge = framePadding.IStart(frameWM);
  }
  nscoord availableISize = aReflowState.AvailableISize();
  NS_ASSERTION(availableISize != NS_UNCONSTRAINEDSIZE,
               "should no longer use available widths");
  // Subtract off inline axis border+padding from availableISize
  availableISize -= startEdge;
  availableISize -= framePadding.IEnd(frameWM);
  lineLayout->BeginSpan(this, &aReflowState, startEdge,
                        startEdge + availableISize, &mBaseline);

  // First reflow our principal children.
  nsIFrame* frame = mFrames.FirstChild();
  bool done = false;
  while (frame) {
    // Check if we should lazily set the child frame's parent pointer.
    if (irs.mSetParentPointer) {
      bool havePrevBlock =
        irs.mLineContainer && irs.mLineContainer->GetPrevContinuation();
      nsIFrame* child = frame;
      do {
        // If our block is the first in flow, then any floats under the pulled
        // frame must already belong to our block.
        if (havePrevBlock) {
          // This has to happen before we update frame's parent; we need to
          // know frame's ancestry under its old block.
          // The blockChildren.ContainsFrame check performed by
          // ReparentFloatsForInlineChild here may be slow, but we can't
          // easily avoid it because we don't know where 'frame' originally
          // came from. If we really really have to optimize this we could
          // cache whether frame->GetParent() is under its containing blocks
          // overflowList or not.
          ReparentFloatsForInlineChild(irs.mLineContainer, child, false);
        }
        child->SetParent(this);
        if (inFirstLine) {
          restyleManager->ReparentStyleContext(child);
          nsLayoutUtils::MarkDescendantsDirty(child);
        }
        // We also need to do the same for |frame|'s next-in-flows that are in
        // the sibling list. Otherwise, if we reflow |frame| and it's complete
        // we'll crash when trying to delete its next-in-flow.
        // This scenario doesn't happen often, but it can happen.
        nsIFrame* nextSibling = child->GetNextSibling();
        child = child->GetNextInFlow();
        if (MOZ_UNLIKELY(child)) {
          while (child != nextSibling && nextSibling) {
            nextSibling = nextSibling->GetNextSibling();
          }
          if (!nextSibling) {
            child = nullptr;
          }
        }
        MOZ_ASSERT(!child || mFrames.ContainsFrame(child));
      } while (child);

      // Fix the parent pointer for ::first-letter child frame next-in-flows,
      // so nsFirstLetterFrame::Reflow can destroy them safely (bug 401042).
      nsIFrame* realFrame = nsPlaceholderFrame::GetRealFrameFor(frame);
      if (realFrame->GetType() == nsGkAtoms::letterFrame) {
        nsIFrame* child = realFrame->GetFirstPrincipalChild();
        if (child) {
          NS_ASSERTION(child->GetType() == nsGkAtoms::textFrame,
                       "unexpected frame type");
          nsIFrame* nextInFlow = child->GetNextInFlow();
          for ( ; nextInFlow; nextInFlow = nextInFlow->GetNextInFlow()) {
            NS_ASSERTION(nextInFlow->GetType() == nsGkAtoms::textFrame,
                         "unexpected frame type");
            if (mFrames.ContainsFrame(nextInFlow)) {
              nextInFlow->SetParent(this);
              if (inFirstLine) {
                restyleManager->ReparentStyleContext(nextInFlow);
                nsLayoutUtils::MarkDescendantsDirty(nextInFlow);
              }
            }
//.........这里部分代码省略.........

void
nsBlockReflowContext::ReflowBlock(const LogicalRect&  aSpace,
                                  bool                aApplyBStartMargin,
                                  nsCollapsingMargin& aPrevMargin,
                                  nscoord             aClearance,
                                  bool                aIsAdjacentWithBStart,
                                  nsLineBox*          aLine,
                                  nsHTMLReflowState&  aFrameRS,
                                  nsReflowStatus&     aFrameReflowStatus,
                                  nsBlockReflowState& aState)
{
  mFrame = aFrameRS.frame;
  mWritingMode = aState.mReflowState.GetWritingMode();
  mContainerSize = aState.ContainerSize();
  mSpace = aSpace;

  if (!aIsAdjacentWithBStart) {
    aFrameRS.mFlags.mIsTopOfPage = false;  // make sure this is cleared
  }

  if (aApplyBStartMargin) {
    mBStartMargin = aPrevMargin;

#ifdef NOISY_BLOCKDIR_MARGINS
    nsFrame::ListTag(stdout, mOuterReflowState.frame);
    printf(": reflowing ");
    nsFrame::ListTag(stdout, mFrame);
    printf(" margin => %d, clearance => %d\n", mBStartMargin.get(), aClearance);
#endif

    // Adjust the available size if it's constrained so that the
    // child frame doesn't think it can reflow into its margin area.
    if (mWritingMode.IsOrthogonalTo(mFrame->GetWritingMode())) {
      if (NS_UNCONSTRAINEDSIZE != aFrameRS.AvailableISize()) {
        aFrameRS.AvailableISize() -= mBStartMargin.get() + aClearance;
      }
    } else {
      if (NS_UNCONSTRAINEDSIZE != aFrameRS.AvailableBSize()) {
        aFrameRS.AvailableBSize() -= mBStartMargin.get() + aClearance;
      }
    }
  }

  nscoord tI = 0, tB = 0;
  // The values of x and y do not matter for floats, so don't bother
  // calculating them. Floats are guaranteed to have their own float
  // manager, so tI and tB don't matter.  mICoord and mBCoord don't
  // matter becacuse they are only used in PlaceBlock, which is not used
  // for floats.
  if (aLine) {
    // Compute inline/block coordinate where reflow will begin. Use the
    // rules from 10.3.3 to determine what to apply. At this point in the
    // reflow auto inline-start/end margins will have a zero value.

    WritingMode frameWM = aFrameRS.GetWritingMode();
    LogicalMargin usedMargin =
      aFrameRS.ComputedLogicalMargin().ConvertTo(mWritingMode, frameWM);
    mICoord = mSpace.IStart(mWritingMode) + usedMargin.IStart(mWritingMode);
    mBCoord = mSpace.BStart(mWritingMode) + mBStartMargin.get() + aClearance;

    LogicalRect space(mWritingMode, mICoord, mBCoord,
                      mSpace.ISize(mWritingMode) -
                      usedMargin.IStartEnd(mWritingMode),
                      mSpace.BSize(mWritingMode) -
                      usedMargin.BStartEnd(mWritingMode));
    tI = space.LineLeft(mWritingMode, mContainerSize);
    tB = mBCoord;

    if ((mFrame->GetStateBits() & NS_BLOCK_FLOAT_MGR) == 0)
      aFrameRS.mBlockDelta =
        mOuterReflowState.mBlockDelta + mBCoord - aLine->BStart();
  }

#ifdef DEBUG
  mMetrics.ISize(mWritingMode) = nscoord(0xdeadbeef);
  mMetrics.BSize(mWritingMode) = nscoord(0xdeadbeef);
#endif

  mOuterReflowState.mFloatManager->Translate(tI, tB);
  mFrame->Reflow(mPresContext, mMetrics, aFrameRS, aFrameReflowStatus);
  mOuterReflowState.mFloatManager->Translate(-tI, -tB);

#ifdef DEBUG
  if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus)) {
    if (CRAZY_SIZE(mMetrics.ISize(mWritingMode)) ||
        CRAZY_SIZE(mMetrics.BSize(mWritingMode))) {
      printf("nsBlockReflowContext: ");
      nsFrame::ListTag(stdout, mFrame);
      printf(" metrics=%d,%d!\n",
             mMetrics.ISize(mWritingMode), mMetrics.BSize(mWritingMode));
    }
    if ((mMetrics.ISize(mWritingMode) == nscoord(0xdeadbeef)) ||
        (mMetrics.BSize(mWritingMode) == nscoord(0xdeadbeef))) {
      printf("nsBlockReflowContext: ");
      nsFrame::ListTag(stdout, mFrame);
      printf(" didn't set i/b %d,%d!\n",
             mMetrics.ISize(mWritingMode), mMetrics.BSize(mWritingMode));
    }
  }
#endif
//.........这里部分代码省略.........

bool
nsColumnSetFrame::ReflowChildren(nsHTMLReflowMetrics&     aDesiredSize,
                                 const nsHTMLReflowState& aReflowState,
                                 nsReflowStatus&          aStatus,
                                 const ReflowConfig&      aConfig,
                                 bool                     aUnboundedLastColumn,
                                 nsCollapsingMargin*      aCarriedOutBEndMargin,
                                 ColumnBalanceData&       aColData)
{
    aColData.Reset();
    bool allFit = true;
    WritingMode wm = GetWritingMode();
    bool isVertical = wm.IsVertical();
    bool isRTL = !wm.IsBidiLTR();
    bool shrinkingBSizeOnly = !NS_SUBTREE_DIRTY(this) &&
                              mLastBalanceBSize > aConfig.mColMaxBSize;

#ifdef DEBUG_roc
    printf("*** Doing column reflow pass: mLastBalanceBSize=%d, mColMaxBSize=%d, RTL=%d\n"
           "    mBalanceColCount=%d, mColISize=%d, mColGap=%d\n",
           mLastBalanceBSize, aConfig.mColMaxBSize, isRTL, aConfig.mBalanceColCount,
           aConfig.mColISize, aConfig.mColGap);
#endif

    DrainOverflowColumns();

    const bool colBSizeChanged = mLastBalanceBSize != aConfig.mColMaxBSize;

    if (colBSizeChanged) {
        mLastBalanceBSize = aConfig.mColMaxBSize;
        // XXX Seems like this could fire if incremental reflow pushed the column set
        // down so we reflow incrementally with a different available height.
        // We need a way to do an incremental reflow and be sure availableHeight
        // changes are taken account of! Right now I think block frames with absolute
        // children might exit early.
        //NS_ASSERTION(aKidReason != eReflowReason_Incremental,
        //             "incremental reflow should not have changed the balance height");
    }

    // get our border and padding
    LogicalMargin borderPadding = aReflowState.ComputedLogicalBorderPadding();
    borderPadding.ApplySkipSides(GetLogicalSkipSides(&aReflowState));

    nsRect contentRect(0, 0, 0, 0);
    nsOverflowAreas overflowRects;

    nsIFrame* child = mFrames.FirstChild();
    LogicalPoint childOrigin(wm, borderPadding.IStart(wm),
                             borderPadding.BStart(wm));
    // In vertical-rl mode, columns will not be correctly placed if the
    // reflowState's ComputedWidth() is UNCONSTRAINED (in which case we'll get
    // a containerSize.width of zero here). In that case, the column positions
    // will be adjusted later, after our correct contentSize is known.
    nsSize containerSize = aReflowState.ComputedSizeAsContainerIfConstrained();

    // For RTL, since the columns might not fill the frame exactly, we
    // need to account for the slop. Otherwise we'll waste time moving the
    // columns by some tiny amount

    // XXX when all of layout is converted to logical coordinates, we
    //     probably won't need to do this hack any more. For now, we
    //     confine it to the legacy horizontal-rl case
    if (!isVertical && isRTL) {
        nscoord availISize = aReflowState.AvailableISize();
        if (aReflowState.ComputedISize() != NS_INTRINSICSIZE) {
            availISize = aReflowState.ComputedISize();
        }
        if (availISize != NS_INTRINSICSIZE) {
            childOrigin.I(wm) = containerSize.width - borderPadding.Left(wm) -
                                availISize;
#ifdef DEBUG_roc
            printf("*** childOrigin.iCoord = %d\n", childOrigin.I(wm));
#endif
        }
    }

    int columnCount = 0;
    int contentBEnd = 0;
    bool reflowNext = false;

    while (child) {
        // Try to skip reflowing the child. We can't skip if the child is dirty. We also can't
        // skip if the next column is dirty, because the next column's first line(s)
        // might be pullable back to this column. We can't skip if it's the last child
        // because we need to obtain the bottom margin. We can't skip
        // if this is the last column and we're supposed to assign unbounded
        // height to it, because that could change the available height from
        // the last time we reflowed it and we should try to pull all the
        // content from its next sibling. (Note that it might be the last
        // column, but not be the last child because the desired number of columns
        // has changed.)
        bool skipIncremental = !aReflowState.ShouldReflowAllKids()
                               && !NS_SUBTREE_DIRTY(child)
                               && child->GetNextSibling()
                               && !(aUnboundedLastColumn && columnCount == aConfig.mBalanceColCount - 1)
                               && !NS_SUBTREE_DIRTY(child->GetNextSibling());
        // If we need to pull up content from the prev-in-flow then this is not just
        // a height shrink. The prev in flow will have set the dirty bit.
        // Check the overflow rect YMost instead of just the child's content height. The child
        // may have overflowing content that cares about the available height boundary.
//.........这里部分代码省略.........