The Tor Browser: layout/generic/nsAbsoluteContainingBlock.cpp@b8a032363ba2 (annotated)

layout/generic/nsAbsoluteContainingBlock.cpp@b8a032363ba2 (annotated)

layout/generic/nsAbsoluteContainingBlock.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- 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/. */
 /*
  * code for managing absolutely positioned children of a rendering
  * object that is a containing block for them
  */
 #include "nsAbsoluteContainingBlock.h"
 #include "nsContainerFrame.h"
 #include "nsGkAtoms.h"
 #include "nsIPresShell.h"
 #include "nsHTMLReflowState.h"
 #include "nsPresContext.h"
 #include "nsCSSFrameConstructor.h"
 #ifdef DEBUG
 #include "nsBlockFrame.h"
 static void PrettyUC(nscoord aSize, char* aBuf)
 {
   if (NS_UNCONSTRAINEDSIZE == aSize) {
     strcpy(aBuf, "UC");
   } else {
     if((int32_t)0xdeadbeef == aSize) {
       strcpy(aBuf, "deadbeef");
     } else {
       sprintf(aBuf, "%d", aSize);
     }
   }
 }
 #endif
 nsresult
 nsAbsoluteContainingBlock::SetInitialChildList(nsIFrame*       aDelegatingFrame,
                                                ChildListID     aListID,
                                                nsFrameList&    aChildList)
 {
   NS_PRECONDITION(mChildListID == aListID, "unexpected child list name");
 #ifdef DEBUG
   nsFrame::VerifyDirtyBitSet(aChildList);
 #endif
   mAbsoluteFrames.SetFrames(aChildList);
   return NS_OK;
 }
 nsresult
 nsAbsoluteContainingBlock::AppendFrames(nsIFrame*      aDelegatingFrame,
                                         ChildListID    aListID,
                                         nsFrameList&   aFrameList)
 {
   NS_ASSERTION(mChildListID == aListID, "unexpected child list");
   // Append the frames to our list of absolutely positioned frames
 #ifdef DEBUG
   nsFrame::VerifyDirtyBitSet(aFrameList);
 #endif
   mAbsoluteFrames.AppendFrames(nullptr, aFrameList);
   // no damage to intrinsic widths, since absolutely positioned frames can't
   // change them
   aDelegatingFrame->PresContext()->PresShell()->
     FrameNeedsReflow(aDelegatingFrame, nsIPresShell::eResize,
                      NS_FRAME_HAS_DIRTY_CHILDREN);
   return NS_OK;
 }
 nsresult
 nsAbsoluteContainingBlock::InsertFrames(nsIFrame*      aDelegatingFrame,
                                         ChildListID    aListID,
                                         nsIFrame*      aPrevFrame,
                                         nsFrameList&   aFrameList)
 {
   NS_ASSERTION(mChildListID == aListID, "unexpected child list");
   NS_ASSERTION(!aPrevFrame || aPrevFrame->GetParent() == aDelegatingFrame,
                "inserting after sibling frame with different parent");
 #ifdef DEBUG
   nsFrame::VerifyDirtyBitSet(aFrameList);
 #endif
   mAbsoluteFrames.InsertFrames(nullptr, aPrevFrame, aFrameList);
   // no damage to intrinsic widths, since absolutely positioned frames can't
   // change them
   aDelegatingFrame->PresContext()->PresShell()->
     FrameNeedsReflow(aDelegatingFrame, nsIPresShell::eResize,
                      NS_FRAME_HAS_DIRTY_CHILDREN);
   return NS_OK;
 }
 void
 nsAbsoluteContainingBlock::RemoveFrame(nsIFrame*       aDelegatingFrame,
                                        ChildListID     aListID,
                                        nsIFrame*       aOldFrame)
 {
   NS_ASSERTION(mChildListID == aListID, "unexpected child list");
   nsIFrame* nif = aOldFrame->GetNextInFlow();
   if (nif) {
     static_cast<nsContainerFrame*>(nif->GetParent())
       ->DeleteNextInFlowChild(nif, false);
   }
   mAbsoluteFrames.DestroyFrame(aOldFrame);
 }
 nsresult
 nsAbsoluteContainingBlock::Reflow(nsContainerFrame*        aDelegatingFrame,
                                   nsPresContext*           aPresContext,
                                   const nsHTMLReflowState& aReflowState,
                                   nsReflowStatus&          aReflowStatus,
                                   const nsRect&            aContainingBlock,
                                   bool                     aConstrainHeight,
                                   bool                     aCBWidthChanged,
                                   bool                     aCBHeightChanged,
                                   nsOverflowAreas*         aOverflowAreas)
 {
   nsReflowStatus reflowStatus = NS_FRAME_COMPLETE;
   bool reflowAll = aReflowState.ShouldReflowAllKids();
   nsIFrame* kidFrame;
   nsOverflowContinuationTracker tracker(aDelegatingFrame, true);
   for (kidFrame = mAbsoluteFrames.FirstChild(); kidFrame; kidFrame = kidFrame->GetNextSibling()) {
     bool kidNeedsReflow = reflowAll || NS_SUBTREE_DIRTY(kidFrame) ||
       FrameDependsOnContainer(kidFrame, aCBWidthChanged, aCBHeightChanged);
     if (kidNeedsReflow && !aPresContext->HasPendingInterrupt()) {
       // Reflow the frame
       nsReflowStatus  kidStatus = NS_FRAME_COMPLETE;
       ReflowAbsoluteFrame(aDelegatingFrame, aPresContext, aReflowState,
                           aContainingBlock,
                           aConstrainHeight, kidFrame, kidStatus,
                           aOverflowAreas);
       nsIFrame* nextFrame = kidFrame->GetNextInFlow();
       if (!NS_FRAME_IS_FULLY_COMPLETE(kidStatus)) {
         // Need a continuation
         if (!nextFrame) {
           nextFrame =
             aPresContext->PresShell()->FrameConstructor()->
               CreateContinuingFrame(aPresContext, kidFrame, aDelegatingFrame);
         }
         // Add it as an overflow container.
         //XXXfr This is a hack to fix some of our printing dataloss.
         // See bug 154892. Not sure how to do it "right" yet; probably want
         // to keep continuations within an nsAbsoluteContainingBlock eventually.
         tracker.Insert(nextFrame, kidStatus);
         NS_MergeReflowStatusInto(&reflowStatus, kidStatus);
       }
       else {
         // Delete any continuations
         if (nextFrame) {
           nsOverflowContinuationTracker::AutoFinish fini(&tracker, kidFrame);
           static_cast<nsContainerFrame*>(nextFrame->GetParent())
             ->DeleteNextInFlowChild(nextFrame, true);
         }
       }
     }
     else {
       tracker.Skip(kidFrame, reflowStatus);
       if (aOverflowAreas) {
         aDelegatingFrame->ConsiderChildOverflow(*aOverflowAreas, kidFrame);
       }
     }
     // Make a CheckForInterrupt call, here, not just HasPendingInterrupt.  That
     // will make sure that we end up reflowing aDelegatingFrame in cases when
     // one of our kids interrupted.  Otherwise we'd set the dirty or
     // dirty-children bit on the kid in the condition below, and then when
     // reflow completes and we go to mark dirty bits on all ancestors of that
     // kid we'll immediately bail out, because the kid already has a dirty bit.
     // In particular, we won't set any dirty bits on aDelegatingFrame, so when
     // the following reflow happens we won't reflow the kid in question.  This
     // might be slightly suboptimal in cases where |kidFrame| itself did not
     // interrupt, since we'll trigger a reflow of it too when it's not strictly
     // needed.  But the logic to not do that is enough more complicated, and
     // the case enough of an edge case, that this is probably better.
     if (kidNeedsReflow && aPresContext->CheckForInterrupt(aDelegatingFrame)) {
       if (aDelegatingFrame->GetStateBits() & NS_FRAME_IS_DIRTY) {
         kidFrame->AddStateBits(NS_FRAME_IS_DIRTY);
       } else {
         kidFrame->AddStateBits(NS_FRAME_HAS_DIRTY_CHILDREN);
       }
     }
   }
   // Abspos frames can't cause their parent to be incomplete,
   // only overflow incomplete.
   if (NS_FRAME_IS_NOT_COMPLETE(reflowStatus))
     NS_FRAME_SET_OVERFLOW_INCOMPLETE(reflowStatus);
   NS_MergeReflowStatusInto(&aReflowStatus, reflowStatus);
   return NS_OK;
 }
 static inline bool IsFixedPaddingSize(const nsStyleCoord& aCoord)
   { return aCoord.ConvertsToLength(); }
 static inline bool IsFixedMarginSize(const nsStyleCoord& aCoord)
   { return aCoord.ConvertsToLength(); }
 static inline bool IsFixedOffset(const nsStyleCoord& aCoord)
   { return aCoord.ConvertsToLength(); }
 bool
 nsAbsoluteContainingBlock::FrameDependsOnContainer(nsIFrame* f,
                                                    bool aCBWidthChanged,
                                                    bool aCBHeightChanged)
 {
   const nsStylePosition* pos = f->StylePosition();
   // See if f's position might have changed because it depends on a
   // placeholder's position
   // This can happen in the following cases:
   // 1) Vertical positioning.  "top" must be auto and "bottom" must be auto
   //    (otherwise the vertical position is completely determined by
   //    whichever of them is not auto and the height).
   // 2) Horizontal positioning.  "left" must be auto and "right" must be auto
   //    (otherwise the horizontal position is completely determined by
   //    whichever of them is not auto and the width).
   // See nsHTMLReflowState::InitAbsoluteConstraints -- these are the
   // only cases when we call CalculateHypotheticalBox().
   if ((pos->mOffset.GetTopUnit() == eStyleUnit_Auto &&
        pos->mOffset.GetBottomUnit() == eStyleUnit_Auto) ||
       (pos->mOffset.GetLeftUnit() == eStyleUnit_Auto &&
        pos->mOffset.GetRightUnit() == eStyleUnit_Auto)) {
     return true;
   }
   if (!aCBWidthChanged && !aCBHeightChanged) {
     // skip getting style data
     return false;
   }
   const nsStylePadding* padding = f->StylePadding();
   const nsStyleMargin* margin = f->StyleMargin();
   if (aCBWidthChanged) {
     // See if f's width might have changed.
     // If border-left, border-right, padding-left, padding-right,
     // width, min-width, and max-width are all lengths, 'none', or enumerated,
     // then our frame width does not depend on the parent width.
     // Note that borders never depend on the parent width
     // XXX All of the enumerated values except -moz-available are ok too.
     if (pos->WidthDependsOnContainer() ||
         pos->MinWidthDependsOnContainer() ||
         pos->MaxWidthDependsOnContainer() ||
         !IsFixedPaddingSize(padding->mPadding.GetLeft()) ||
         !IsFixedPaddingSize(padding->mPadding.GetRight())) {
       return true;
     }
     // See if f's position might have changed. If we're RTL then the
     // rules are slightly different. We'll assume percentage or auto
     // margins will always induce a dependency on the size
     if (!IsFixedMarginSize(margin->mMargin.GetLeft()) ||
         !IsFixedMarginSize(margin->mMargin.GetRight())) {
       return true;
     }
     if (f->StyleVisibility()->mDirection == NS_STYLE_DIRECTION_RTL) {
       // Note that even if 'left' is a length, our position can
       // still depend on the containing block width, because if
       // 'right' is also a length we will discard 'left' and be
       // positioned relative to the containing block right edge.
       // 'left' length and 'right' auto is the only combination
       // we can be sure of.
       if (!IsFixedOffset(pos->mOffset.GetLeft()) ||
           pos->mOffset.GetRightUnit() != eStyleUnit_Auto) {
         return true;
       }
     } else {
       if (!IsFixedOffset(pos->mOffset.GetLeft())) {
         return true;
       }
     }
   }
   if (aCBHeightChanged) {
     // See if f's height might have changed.
     // If border-top, border-bottom, padding-top, padding-bottom,
     // min-height, and max-height are all lengths or 'none',
     // and height is a length or height and bottom are auto and top is not auto,
     // then our frame height does not depend on the parent height.
     // Note that borders never depend on the parent height
     if ((pos->HeightDependsOnContainer() &&
          !(pos->mHeight.GetUnit() == eStyleUnit_Auto &&
            pos->mOffset.GetBottomUnit() == eStyleUnit_Auto &&
            pos->mOffset.GetTopUnit() != eStyleUnit_Auto)) ||
         pos->MinHeightDependsOnContainer() ||
         pos->MaxHeightDependsOnContainer() ||
         !IsFixedPaddingSize(padding->mPadding.GetTop()) ||
         !IsFixedPaddingSize(padding->mPadding.GetBottom())) {
       return true;
     }
     // See if f's position might have changed.
     if (!IsFixedMarginSize(margin->mMargin.GetTop()) ||
         !IsFixedMarginSize(margin->mMargin.GetBottom())) {
       return true;
     }
     if (!IsFixedOffset(pos->mOffset.GetTop())) {
       return true;
     }
   }
   return false;
 }
 void
 nsAbsoluteContainingBlock::DestroyFrames(nsIFrame* aDelegatingFrame,
                                          nsIFrame* aDestructRoot)
 {
   mAbsoluteFrames.DestroyFramesFrom(aDestructRoot);
 }
 void
 nsAbsoluteContainingBlock::MarkSizeDependentFramesDirty()
 {
   DoMarkFramesDirty(false);
 }
 void
 nsAbsoluteContainingBlock::MarkAllFramesDirty()
 {
   DoMarkFramesDirty(true);
 }
 void
 nsAbsoluteContainingBlock::DoMarkFramesDirty(bool aMarkAllDirty)
 {
   for (nsIFrame* kidFrame = mAbsoluteFrames.FirstChild();
        kidFrame;
        kidFrame = kidFrame->GetNextSibling()) {
     if (aMarkAllDirty) {
       kidFrame->AddStateBits(NS_FRAME_IS_DIRTY);
     } else if (FrameDependsOnContainer(kidFrame, true, true)) {
       // Add the weakest flags that will make sure we reflow this frame later
       kidFrame->AddStateBits(NS_FRAME_HAS_DIRTY_CHILDREN);
     }
   }
 }
 // XXX Optimize the case where it's a resize reflow and the absolutely
 // positioned child has the exact same size and position and skip the
 // reflow...
 // When bug 154892 is checked in, make sure that when
 // mChildListID == kFixedList, the height is unconstrained.
 // since we don't allow replicated frames to split.
 nsresult
 nsAbsoluteContainingBlock::ReflowAbsoluteFrame(nsIFrame*                aDelegatingFrame,
                                                nsPresContext*           aPresContext,
                                                const nsHTMLReflowState& aReflowState,
                                                const nsRect&            aContainingBlock,
                                                bool                     aConstrainHeight,
                                                nsIFrame*                aKidFrame,
                                                nsReflowStatus&          aStatus,
                                                nsOverflowAreas*         aOverflowAreas)
 {
 #ifdef DEBUG
   if (nsBlockFrame::gNoisyReflow) {
     nsFrame::IndentBy(stdout,nsBlockFrame::gNoiseIndent);
     printf("abs pos ");
     if (aKidFrame) {
       nsAutoString name;
       aKidFrame->GetFrameName(name);
       printf("%s ", NS_LossyConvertUTF16toASCII(name).get());
     }
     char width[16];
     char height[16];
     PrettyUC(aReflowState.AvailableWidth(), width);
     PrettyUC(aReflowState.AvailableHeight(), height);
     printf(" a=%s,%s ", width, height);
     PrettyUC(aReflowState.ComputedWidth(), width);
     PrettyUC(aReflowState.ComputedHeight(), height);
     printf("c=%s,%s \n", width, height);
   }
   AutoNoisyIndenter indent(nsBlockFrame::gNoisy);
 #endif // DEBUG
   nscoord availWidth = aContainingBlock.width;
   if (availWidth == -1) {
     NS_ASSERTION(aReflowState.ComputedWidth() != NS_UNCONSTRAINEDSIZE,
                  "Must have a useful width _somewhere_");
     availWidth =
       aReflowState.ComputedWidth() + aReflowState.ComputedPhysicalPadding().LeftRight();
   }
   nsHTMLReflowMetrics kidDesiredSize(aReflowState);
   nsHTMLReflowState kidReflowState(aPresContext, aReflowState, aKidFrame,
                                    nsSize(availWidth, NS_UNCONSTRAINEDSIZE),
                                    aContainingBlock.width,
                                    aContainingBlock.height);
   // Send the WillReflow() notification and position the frame
   aKidFrame->WillReflow(aPresContext);
   // Get the border values
   const nsMargin& border = aReflowState.mStyleBorder->GetComputedBorder();
   bool constrainHeight = (aReflowState.AvailableHeight() != NS_UNCONSTRAINEDSIZE)
     && aConstrainHeight
        // Don't split if told not to (e.g. for fixed frames)
     && (aDelegatingFrame->GetType() != nsGkAtoms::inlineFrame)
        //XXX we don't handle splitting frames for inline absolute containing blocks yet
     && (aKidFrame->GetRect().y <= aReflowState.AvailableHeight());
        // Don't split things below the fold. (Ideally we shouldn't *have*
        // anything totally below the fold, but we can't position frames
        // across next-in-flow breaks yet.
   if (constrainHeight) {
     kidReflowState.AvailableHeight() = aReflowState.AvailableHeight() - border.top
                                      - kidReflowState.ComputedPhysicalMargin().top;
     if (NS_AUTOOFFSET != kidReflowState.ComputedPhysicalOffsets().top)
       kidReflowState.AvailableHeight() -= kidReflowState.ComputedPhysicalOffsets().top;
   }
   // Do the reflow
   nsresult rv = aKidFrame->Reflow(aPresContext, kidDesiredSize, kidReflowState, aStatus);
   // If we're solving for 'left' or 'top', then compute it now that we know the
   // width/height
   if ((NS_AUTOOFFSET == kidReflowState.ComputedPhysicalOffsets().left) ||
       (NS_AUTOOFFSET == kidReflowState.ComputedPhysicalOffsets().top)) {
     nscoord aContainingBlockWidth = aContainingBlock.width;
     nscoord aContainingBlockHeight = aContainingBlock.height;
     if (-1 == aContainingBlockWidth) {
       // Get the containing block width/height
       kidReflowState.ComputeContainingBlockRectangle(aPresContext,
                                                      &aReflowState,
                                                      aContainingBlockWidth,
                                                      aContainingBlockHeight);
     }
     if (NS_AUTOOFFSET == kidReflowState.ComputedPhysicalOffsets().left) {
       NS_ASSERTION(NS_AUTOOFFSET != kidReflowState.ComputedPhysicalOffsets().right,
                    "Can't solve for both left and right");
       kidReflowState.ComputedPhysicalOffsets().left = aContainingBlockWidth -
                                              kidReflowState.ComputedPhysicalOffsets().right -
                                              kidReflowState.ComputedPhysicalMargin().right -
                                              kidDesiredSize.Width() -
                                              kidReflowState.ComputedPhysicalMargin().left;
     }
     if (NS_AUTOOFFSET == kidReflowState.ComputedPhysicalOffsets().top) {
       kidReflowState.ComputedPhysicalOffsets().top = aContainingBlockHeight -
                                             kidReflowState.ComputedPhysicalOffsets().bottom -
                                             kidReflowState.ComputedPhysicalMargin().bottom -
                                             kidDesiredSize.Height() -
                                             kidReflowState.ComputedPhysicalMargin().top;
     }
   }
   // Position the child relative to our padding edge
   nsRect  rect(border.left + kidReflowState.ComputedPhysicalOffsets().left + kidReflowState.ComputedPhysicalMargin().left,
                border.top + kidReflowState.ComputedPhysicalOffsets().top + kidReflowState.ComputedPhysicalMargin().top,
                kidDesiredSize.Width(), kidDesiredSize.Height());
   // Offset the frame rect by the given origin of the absolute containing block.
   // If the frame is auto-positioned on both sides of an axis, it will be
   // positioned based on its containing block and we don't need to offset.
   if (aContainingBlock.TopLeft() != nsPoint(0, 0)) {
     if (!(kidReflowState.mStylePosition->mOffset.GetLeftUnit() == eStyleUnit_Auto &&
           kidReflowState.mStylePosition->mOffset.GetRightUnit() == eStyleUnit_Auto)) {
       rect.x += aContainingBlock.x;
     }
     if (!(kidReflowState.mStylePosition->mOffset.GetTopUnit() == eStyleUnit_Auto &&
           kidReflowState.mStylePosition->mOffset.GetBottomUnit() == eStyleUnit_Auto)) {
       rect.y += aContainingBlock.y;
     }
   }
   aKidFrame->SetRect(rect);
   nsView* view = aKidFrame->GetView();
   if (view) {
     // Size and position the view and set its opacity, visibility, content
     // transparency, and clip
     nsContainerFrame::SyncFrameViewAfterReflow(aPresContext, aKidFrame, view,
                                                kidDesiredSize.VisualOverflow());
   } else {
     nsContainerFrame::PositionChildViews(aKidFrame);
   }
   aKidFrame->DidReflow(aPresContext, &kidReflowState, nsDidReflowStatus::FINISHED);
 #ifdef DEBUG
   if (nsBlockFrame::gNoisyReflow) {
     nsFrame::IndentBy(stdout,nsBlockFrame::gNoiseIndent - 1);
     printf("abs pos ");
     if (aKidFrame) {
       nsAutoString name;
       aKidFrame->GetFrameName(name);
       printf("%s ", NS_LossyConvertUTF16toASCII(name).get());
     }
     printf("%p rect=%d,%d,%d,%d\n", static_cast<void*>(aKidFrame),
            rect.x, rect.y, rect.width, rect.height);
   }
 #endif
   if (aOverflowAreas) {
     aOverflowAreas->UnionWith(kidDesiredSize.mOverflowAreas + rect.TopLeft());
   }
   return rv;
 }

The Tor Browser / annotate

layout/generic/nsAbsoluteContainingBlock.cpp@b8a032363ba2 (annotated)

layout/generic/nsAbsoluteContainingBlock.cpp