layout/generic/nsFirstLetterFrame.cpp
author Nika Layzell <nika@thelayzells.com>
Tue, 25 Sep 2018 17:34:53 +0200
changeset 507828 5e6dae0c1e5a4939ccd406f14607f7fafffd45a7
parent 489418 6605ef249363dcf770e4d07d9753b2252690d1f2
child 508163 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1448426 - Wrap windows.h to avoid problematic define statements, r=froydnj,glandium By default, windows.h exposes a large number of problematic define statements which are UpperCamelCase, such as a define from `CreateWindow` to `CreateWindow{A,W}`. As many of these names are generic (e.g. CreateFile, CreateWindow), they can mess up Gecko code that may legitimately have its own methods with the same names. The header also defines some traditional SCREAMING_SNAKE_CASE defines which can mess up our code by conflicting with local values. This patch adds a simple code generator which generates wrappers for these defines, and uses them to wrap the windows.h wrapper using the `stl_wrappers` mechanism, allowing us to use windows.h in more places. Differential Revision: https://phabricator.services.mozilla.com/D10932

/* -*- 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
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/* rendering object for CSS :first-letter pseudo-element */

#include "nsFirstLetterFrame.h"
#include "nsPresContext.h"
#include "mozilla/ComputedStyle.h"
#include "nsIContent.h"
#include "nsLineLayout.h"
#include "nsGkAtoms.h"
#include "mozilla/ServoStyleSet.h"
#include "nsFrameManager.h"
#include "mozilla/RestyleManager.h"
#include "nsPlaceholderFrame.h"
#include "nsCSSFrameConstructor.h"

using namespace mozilla;
using namespace mozilla::layout;

nsFirstLetterFrame*
NS_NewFirstLetterFrame(nsIPresShell* aPresShell, ComputedStyle* aStyle)
{
  return new (aPresShell) nsFirstLetterFrame(aStyle);
}

NS_IMPL_FRAMEARENA_HELPERS(nsFirstLetterFrame)

NS_QUERYFRAME_HEAD(nsFirstLetterFrame)
  NS_QUERYFRAME_ENTRY(nsFirstLetterFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)

#ifdef DEBUG_FRAME_DUMP
nsresult
nsFirstLetterFrame::GetFrameName(nsAString& aResult) const
{
  return MakeFrameName(NS_LITERAL_STRING("Letter"), aResult);
}
#endif

void
nsFirstLetterFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                     const nsDisplayListSet& aLists)
{
  BuildDisplayListForInline(aBuilder, aLists);
}

void
nsFirstLetterFrame::Init(nsIContent*       aContent,
                         nsContainerFrame* aParent,
                         nsIFrame*         aPrevInFlow)
{
  RefPtr<ComputedStyle> newSC;
  if (aPrevInFlow) {
    // Get proper ComputedStyle for ourselves.  We're creating the frame
    // that represents everything *except* the first letter, so just create
    // a ComputedStyle that inherits from our style parent, with no extra rules.
    nsIFrame* styleParent =
      CorrectStyleParentFrame(aParent, nsCSSPseudoElements::firstLetter());
    ComputedStyle* parentComputedStyle = styleParent->Style();
    newSC = PresContext()->StyleSet()->
      ResolveStyleForFirstLetterContinuation(parentComputedStyle);
    SetComputedStyleWithoutNotification(newSC);
  }

  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
}

void
nsFirstLetterFrame::SetInitialChildList(ChildListID  aListID,
                                        nsFrameList& aChildList)
{
  MOZ_ASSERT(aListID == kPrincipalList, "Principal child list is the only "
             "list that nsFirstLetterFrame should set via this function");
  for (nsIFrame* f : aChildList) {
    MOZ_ASSERT(f->GetParent() == this, "Unexpected parent");
    MOZ_ASSERT(f->IsTextFrame(), "We should not have kids that are containers!");
    nsLayoutUtils::MarkDescendantsDirty(f); // Drops cached textruns
  }

  mFrames.SetFrames(aChildList);
}

nsresult
nsFirstLetterFrame::GetChildFrameContainingOffset(int32_t inContentOffset,
                                                  bool inHint,
                                                  int32_t* outFrameContentOffset,
                                                  nsIFrame **outChildFrame)
{
  nsIFrame *kid = mFrames.FirstChild();
  if (kid) {
    return kid->GetChildFrameContainingOffset(inContentOffset, inHint, outFrameContentOffset, outChildFrame);
  } else {
    return nsFrame::GetChildFrameContainingOffset(inContentOffset, inHint, outFrameContentOffset, outChildFrame);
  }
}

// Needed for non-floating first-letter frames and for the continuations
// following the first-letter that we also use nsFirstLetterFrame for.
/* virtual */ void
nsFirstLetterFrame::AddInlineMinISize(gfxContext *aRenderingContext,
                                      nsIFrame::InlineMinISizeData *aData)
{
  DoInlineIntrinsicISize(aRenderingContext, aData, nsLayoutUtils::MIN_ISIZE);
}

// Needed for non-floating first-letter frames and for the continuations
// following the first-letter that we also use nsFirstLetterFrame for.
/* virtual */ void
nsFirstLetterFrame::AddInlinePrefISize(gfxContext *aRenderingContext,
                                       nsIFrame::InlinePrefISizeData *aData)
{
  DoInlineIntrinsicISize(aRenderingContext, aData, nsLayoutUtils::PREF_ISIZE);
  aData->mLineIsEmpty = false;
}

// Needed for floating first-letter frames.
/* virtual */ nscoord
nsFirstLetterFrame::GetMinISize(gfxContext *aRenderingContext)
{
  return nsLayoutUtils::MinISizeFromInline(this, aRenderingContext);
}

// Needed for floating first-letter frames.
/* virtual */ nscoord
nsFirstLetterFrame::GetPrefISize(gfxContext *aRenderingContext)
{
  return nsLayoutUtils::PrefISizeFromInline(this, aRenderingContext);
}

/* virtual */
LogicalSize
nsFirstLetterFrame::ComputeSize(gfxContext *aRenderingContext,
                                WritingMode aWM,
                                const LogicalSize& aCBSize,
                                nscoord aAvailableISize,
                                const LogicalSize& aMargin,
                                const LogicalSize& aBorder,
                                const LogicalSize& aPadding,
                                ComputeSizeFlags aFlags)
{
  if (GetPrevInFlow()) {
    // We're wrapping the text *after* the first letter, so behave like an
    // inline frame.
    return LogicalSize(aWM, NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
  }
  return nsContainerFrame::ComputeSize(aRenderingContext, aWM,
      aCBSize, aAvailableISize, aMargin, aBorder, aPadding, aFlags);
}

void
nsFirstLetterFrame::Reflow(nsPresContext*          aPresContext,
                           ReflowOutput&     aMetrics,
                           const ReflowInput& aReflowInput,
                           nsReflowStatus&          aReflowStatus)
{
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsFirstLetterFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowInput, aMetrics, aReflowStatus);
  MOZ_ASSERT(aReflowStatus.IsEmpty(), "Caller should pass a fresh reflow status!");

  // Grab overflow list
  DrainOverflowFrames(aPresContext);

  nsIFrame* kid = mFrames.FirstChild();

  // Setup reflow state for our child
  WritingMode wm = aReflowInput.GetWritingMode();
  LogicalSize availSize = aReflowInput.AvailableSize();
  const LogicalMargin& bp = aReflowInput.ComputedLogicalBorderPadding();
  NS_ASSERTION(availSize.ISize(wm) != NS_UNCONSTRAINEDSIZE,
               "should no longer use unconstrained inline size");
  availSize.ISize(wm) -= bp.IStartEnd(wm);
  if (NS_UNCONSTRAINEDSIZE != availSize.BSize(wm)) {
    availSize.BSize(wm) -= bp.BStartEnd(wm);
  }

  WritingMode lineWM = aMetrics.GetWritingMode();
  ReflowOutput kidMetrics(lineWM);

  // Reflow the child
  if (!aReflowInput.mLineLayout) {
    // When there is no lineLayout provided, we provide our own. The
    // only time that the first-letter-frame is not reflowing in a
    // line context is when its floating.
    WritingMode kidWritingMode = WritingModeForLine(wm, kid);
    LogicalSize kidAvailSize = availSize.ConvertTo(kidWritingMode, wm);
    ReflowInput rs(aPresContext, aReflowInput, kid, kidAvailSize);
    nsLineLayout ll(aPresContext, nullptr, &aReflowInput, nullptr, nullptr);

    ll.BeginLineReflow(bp.IStart(wm), bp.BStart(wm),
                       availSize.ISize(wm), NS_UNCONSTRAINEDSIZE,
                       false, true, kidWritingMode,
                       nsSize(aReflowInput.AvailableWidth(),
                              aReflowInput.AvailableHeight()));
    rs.mLineLayout = &ll;
    ll.SetInFirstLetter(true);
    ll.SetFirstLetterStyleOK(true);

    kid->Reflow(aPresContext, kidMetrics, rs, aReflowStatus);

    ll.EndLineReflow();
    ll.SetInFirstLetter(false);

    // In the floating first-letter case, we need to set this ourselves;
    // nsLineLayout::BeginSpan will set it in the other case
    mBaseline = kidMetrics.BlockStartAscent();

    // Place and size the child and update the output metrics
    LogicalSize convertedSize = kidMetrics.Size(lineWM).ConvertTo(wm, lineWM);
    kid->SetRect(nsRect(bp.IStart(wm), bp.BStart(wm),
                        convertedSize.ISize(wm), convertedSize.BSize(wm)));
    kid->FinishAndStoreOverflow(&kidMetrics, rs.mStyleDisplay);
    kid->DidReflow(aPresContext, nullptr);

    convertedSize.ISize(wm) += bp.IStartEnd(wm);
    convertedSize.BSize(wm) += bp.BStartEnd(wm);
    aMetrics.SetSize(wm, convertedSize);
    aMetrics.SetBlockStartAscent(kidMetrics.BlockStartAscent() +
                                 bp.BStart(wm));

    // Ensure that the overflow rect contains the child textframe's
    // overflow rect.
    // Note that if this is floating, the overline/underline drawable
    // area is in the overflow rect of the child textframe.
    aMetrics.UnionOverflowAreasWithDesiredBounds();
    ConsiderChildOverflow(aMetrics.mOverflowAreas, kid);

    FinishAndStoreOverflow(&aMetrics, aReflowInput.mStyleDisplay);
  } else {
    // Pretend we are a span and reflow the child frame
    nsLineLayout* ll = aReflowInput.mLineLayout;
    bool          pushedFrame;

    ll->SetInFirstLetter(
      mComputedStyle->GetPseudo() == nsCSSPseudoElements::firstLetter());
    ll->BeginSpan(this, &aReflowInput, bp.IStart(wm),
                  availSize.ISize(wm), &mBaseline);
    ll->ReflowFrame(kid, aReflowStatus, &kidMetrics, pushedFrame);
    NS_ASSERTION(lineWM.IsVertical() == wm.IsVertical(),
                 "we're assuming we can mix sizes between lineWM and wm "
                 "since we shouldn't have orthogonal writing modes within "
                 "a line.");
    aMetrics.ISize(lineWM) = ll->EndSpan(this) + bp.IStartEnd(wm);
    ll->SetInFirstLetter(false);

    if (mComputedStyle->StyleTextReset()->mInitialLetterSize != 0.0f) {
      aMetrics.SetBlockStartAscent(kidMetrics.BlockStartAscent() +
                                   bp.BStart(wm));
      aMetrics.BSize(lineWM) = kidMetrics.BSize(lineWM) + bp.BStartEnd(wm);
    } else {
      nsLayoutUtils::SetBSizeFromFontMetrics(this, aMetrics, bp, lineWM, wm);
    }
  }

  if (!aReflowStatus.IsInlineBreakBefore()) {
    // Create a continuation or remove existing continuations based on
    // the reflow completion status.
    if (aReflowStatus.IsComplete()) {
      if (aReflowInput.mLineLayout) {
        aReflowInput.mLineLayout->SetFirstLetterStyleOK(false);
      }
      nsIFrame* kidNextInFlow = kid->GetNextInFlow();
      if (kidNextInFlow) {
        // Remove all of the childs next-in-flows
        kidNextInFlow->GetParent()->DeleteNextInFlowChild(kidNextInFlow, true);
      }
    } else {
      // Create a continuation for the child frame if it doesn't already
      // have one.
      if (!IsFloating()) {
        CreateNextInFlow(kid);
        // And then push it to our overflow list
        const nsFrameList& overflow = mFrames.RemoveFramesAfter(kid);
        if (overflow.NotEmpty()) {
          SetOverflowFrames(overflow);
        }
      } else if (!kid->GetNextInFlow()) {
        // For floating first letter frames (if a continuation wasn't already
        // created for us) we need to put the continuation with the rest of the
        // text that the first letter frame was made out of.
        nsIFrame* continuation;
        CreateContinuationForFloatingParent(aPresContext, kid,
                                            &continuation, true);
      }
    }
  }

  NS_FRAME_SET_TRUNCATION(aReflowStatus, aReflowInput, aMetrics);
}

/* virtual */ bool
nsFirstLetterFrame::CanContinueTextRun() const
{
  // We can continue a text run through a first-letter frame.
  return true;
}

nsresult
nsFirstLetterFrame::CreateContinuationForFloatingParent(nsPresContext* aPresContext,
                                                        nsIFrame* aChild,
                                                        nsIFrame** aContinuation,
                                                        bool aIsFluid)
{
  NS_ASSERTION(IsFloating(),
               "can only call this on floating first letter frames");
  MOZ_ASSERT(aContinuation, "bad args");

  *aContinuation = nullptr;

  nsIPresShell* presShell = aPresContext->PresShell();
  nsPlaceholderFrame* placeholderFrame = GetPlaceholderFrame();
  nsContainerFrame* parent = placeholderFrame->GetParent();

  nsIFrame* continuation = presShell->FrameConstructor()->
    CreateContinuingFrame(aPresContext, aChild, parent, aIsFluid);

  // The continuation will have gotten the first letter style from its
  // prev continuation, so we need to repair the ComputedStyle so it
  // doesn't have the first letter styling.
  //
  // Note that getting parent frame's ComputedStyle is different from getting
  // this frame's ComputedStyle's parent in the presence of ::first-line,
  // which we do want the continuation to inherit from.
  ComputedStyle* parentSC = parent->Style();
  if (parentSC) {
    RefPtr<ComputedStyle> newSC;
    newSC = presShell->StyleSet()->ResolveStyleForFirstLetterContinuation(parentSC);
    continuation->SetComputedStyle(newSC);
    nsLayoutUtils::MarkDescendantsDirty(continuation);
  }

  //XXX Bidi may not be involved but we have to use the list name
  // kNoReflowPrincipalList because this is just like creating a continuation
  // except we have to insert it in a different place and we don't want a
  // reflow command to try to be issued.
  nsFrameList temp(continuation, continuation);
  parent->InsertFrames(kNoReflowPrincipalList, placeholderFrame, temp);

  *aContinuation = continuation;
  return NS_OK;
}

void
nsFirstLetterFrame::DrainOverflowFrames(nsPresContext* aPresContext)
{
  // Check for an overflow list with our prev-in-flow
  nsFirstLetterFrame* prevInFlow = (nsFirstLetterFrame*)GetPrevInFlow();
  if (prevInFlow) {
    AutoFrameListPtr overflowFrames(aPresContext,
                                    prevInFlow->StealOverflowFrames());
    if (overflowFrames) {
      NS_ASSERTION(mFrames.IsEmpty(), "bad overflow list");

      // When pushing and pulling frames we need to check for whether any
      // views need to be reparented.
      nsContainerFrame::ReparentFrameViewList(*overflowFrames, prevInFlow,
                                              this);
      mFrames.InsertFrames(this, nullptr, *overflowFrames);
    }
  }

  // It's also possible that we have an overflow list for ourselves
  AutoFrameListPtr overflowFrames(aPresContext, StealOverflowFrames());
  if (overflowFrames) {
    NS_ASSERTION(mFrames.NotEmpty(), "overflow list w/o frames");
    mFrames.AppendFrames(nullptr, *overflowFrames);
  }

  // Now repair our first frames ComputedStyle (since we only reflow
  // one frame there is no point in doing any other ones until they
  // are reflowed)
  nsIFrame* kid = mFrames.FirstChild();
  if (kid) {
    nsIContent* kidContent = kid->GetContent();
    if (kidContent) {
      NS_ASSERTION(kidContent->IsText(),
                   "should contain only text nodes");
      ComputedStyle* parentSC;
      if (prevInFlow) {
        // This is for the rest of the content not in the first-letter.
        nsIFrame* styleParent =
          CorrectStyleParentFrame(GetParent(),
                                  nsCSSPseudoElements::firstLetter());
        parentSC = styleParent->Style();
      } else {
        // And this for the first-letter style.
        parentSC = mComputedStyle;
      }
      RefPtr<ComputedStyle> sc =
        aPresContext->StyleSet()->ResolveStyleForText(kidContent, parentSC);
      kid->SetComputedStyle(sc);
      nsLayoutUtils::MarkDescendantsDirty(kid);
    }
  }
}

nscoord
nsFirstLetterFrame::GetLogicalBaseline(WritingMode aWritingMode) const
{
  return mBaseline;
}

nsIFrame::LogicalSides
nsFirstLetterFrame::GetLogicalSkipSides(const ReflowInput* aReflowInput) const
{
  if (GetPrevContinuation()) {
    // We shouldn't get calls to GetSkipSides for later continuations since
    // they have separate ComputedStyles with initial values for all the
    // properties that could trigger a call to GetSkipSides.  Then again,
    // it's not really an error to call GetSkipSides on any frame, so
    // that's why we handle it properly.
    return LogicalSides(eLogicalSideBitsAll);
  }
  return LogicalSides();  // first continuation displays all sides
}