File indexing completed on 2025-04-27 10:07:22

 /**
  * This file is part of the html renderer for KDE.
  *
  * Copyright (C) 2000-2003 Lars Knoll (knoll@kde.org)
  *           (C) 2003-2007 Apple Computer, Inc.
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2007-2009 Germain Garand (germain@ebooksfrance.org)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 #include "rendering/bidi.h"
 #include "rendering/break_lines.h"
 #include "rendering/render_block.h"
 #include "rendering/render_text.h"
 #include "rendering/render_arena.h"
 #include "rendering/render_layer.h"
 #include "rendering/render_canvas.h"
 #include "xml/dom_docimpl.h"
 #include <QVector>
 
 #include "QDebug"
 
 #include <limits.h>
 
 // SVG
 #include "rendering/SVGRootInlineBox.h"
 #include "rendering/SVGInlineTextBox.h"
 
 #define BIDI_DEBUG 0
 //#define DEBUG_LINEBREAKS
 //#define PAGE_DEBUG
 
 namespace khtml
 {
 
 // an iterator which goes through a BidiParagraph
 struct BidiIterator {
     BidiIterator() : par(nullptr), obj(nullptr), pos(0), endOfInline(false) {}
     BidiIterator(RenderBlock *_par, RenderObject *_obj, unsigned int _pos, bool eoi = false) : par(_par), obj(_obj), pos(_pos), endOfInline(eoi) {}
 
     void increment(BidiState *bidi = nullptr, bool skipInlines = true);
 
     bool atEnd() const;
 
     const QChar &current() const;
     QChar::Direction direction() const;
 
     RenderBlock *par;
     RenderObject *obj;
     unsigned int pos;
     bool endOfInline;
 };
 
 struct BidiState {
     BidiState() : context(nullptr) {}
 
     BidiIterator sor;
     BidiIterator eor;
     BidiIterator last;
     BidiIterator current;
     BidiContext *context;
     BidiStatus status;
 };
 
 // Used to track a list of chained bidi runs.
 static BidiRun *sFirstBidiRun;
 static BidiRun *sLastBidiRun;
 static int sBidiRunCount;
 static BidiRun *sCompactFirstBidiRun;
 static BidiRun *sCompactLastBidiRun;
 static int sCompactBidiRunCount;
 static bool sBuildingCompactRuns;
 
 // Midpoint globals.  The goal is not to do any allocation when dealing with
 // these midpoints, so we just keep an array around and never clear it.  We track
 // the number of items and position using the two other variables.
 static QVector<BidiIterator> *smidpoints;
 static uint sNumMidpoints;
 static uint sCurrMidpoint;
 static bool betweenMidpoints;
 
 static bool isLineEmpty = true;
 static bool previousLineBrokeAtBR = false;
 static QChar::Direction dir = QChar::DirON;
 static bool emptyRun = true;
 static int numSpaces;
 
 static void embed(QChar::Direction d, BidiState &bidi);
 static void appendRun(BidiState &bidi);
 
 static int getBPMWidth(int childValue, Length cssUnit)
 {
     if (!cssUnit.isAuto()) {
         return (cssUnit.isFixed() ? cssUnit.value() : childValue);
     }
     return 0;
 }
 
 static int getBorderPaddingMargin(RenderObject *child, bool endOfInline)
 {
     RenderStyle *cstyle = child->style();
     int result = 0;
     bool leftSide = (cstyle->direction() == LTR) ? !endOfInline : endOfInline;
     result += getBPMWidth((leftSide ? child->marginLeft() : child->marginRight()),
                           (leftSide ? cstyle->marginLeft() :
                            cstyle->marginRight()));
     result += getBPMWidth((leftSide ? child->paddingLeft() : child->paddingRight()),
                           (leftSide ? cstyle->paddingLeft() :
                            cstyle->paddingRight()));
     result += leftSide ? child->borderLeft() : child->borderRight();
     return result;
 }
 
 #ifndef NDEBUG
 static bool inBidiRunDetach;
 #endif
 
 void BidiRun::detach(RenderArena *renderArena)
 {
 #ifndef NDEBUG
     inBidiRunDetach = true;
 #endif
     delete this;
 #ifndef NDEBUG
     inBidiRunDetach = false;
 #endif
 
     // Recover the size left there for us by operator delete and free the memory.
     renderArena->free(*(size_t *)this, this);
 }
 
 void *BidiRun::operator new(size_t sz, RenderArena *renderArena) throw()
 {
     return renderArena->allocate(sz);
 }
 
 void BidiRun::operator delete(void *ptr, size_t sz)
 {
     assert(inBidiRunDetach);
 
     // Stash size where detach can find it.
     *(size_t *)ptr = sz;
 }
 
 static void deleteBidiRuns(RenderArena *arena)
 {
     if (!sFirstBidiRun) {
         return;
     }
 
     BidiRun *curr = sFirstBidiRun;
     while (curr) {
         BidiRun *s = curr->nextRun;
         curr->detach(arena);
         curr = s;
     }
 
     sFirstBidiRun = nullptr;
     sLastBidiRun = nullptr;
     sBidiRunCount = 0;
 }
 
 // ---------------------------------------------------------------------
 
 /* a small helper class used internally to resolve Bidi embedding levels.
    Each line of text caches the embedding level at the start of the line for faster
    relayouting
 */
 BidiContext::BidiContext(unsigned char l, QChar::Direction e, BidiContext *p, bool o)
     : level(l), override(o), dir(e)
 {
     parent = p;
     if (p) {
         p->ref();
         basicDir = p->basicDir;
     } else {
         basicDir = e;
     }
     count = 0;
 }
 
 BidiContext::~BidiContext()
 {
     if (parent) {
         parent->deref();
     }
 }
 
 void BidiContext::ref() const
 {
     count++;
 }
 
 void BidiContext::deref() const
 {
     count--;
     if (count <= 0) {
         delete this;
     }
 }
 
 // ---------------------------------------------------------------------
 
 inline bool operator==(const BidiContext &c1, const BidiContext &c2)
 {
     if (&c1 == &c2) {
         return true;
     }
     if (c1.level != c2.level || c1.override != c2.override || c1.dir != c2.dir || c1.basicDir != c2.basicDir) {
         return false;
     }
     if (!c1.parent) {
         return !c2.parent;
     }
     return c2.parent && *c1.parent == *c2.parent;
 }
 
 inline bool operator==(const BidiIterator &it1, const BidiIterator &it2)
 {
     if (it1.pos != it2.pos) {
         return false;
     }
     if (it1.obj != it2.obj) {
         return false;
     }
     return true;
 }
 
 inline bool operator!=(const BidiIterator &it1, const BidiIterator &it2)
 {
     if (it1.pos != it2.pos) {
         return true;
     }
     if (it1.obj != it2.obj) {
         return true;
     }
     return false;
 }
 
 inline bool operator==(const BidiStatus &status1, const BidiStatus &status2)
 {
     return status1.eor == status2.eor && status1.last == status2.last && status1.lastStrong == status2.lastStrong;
 }
 
 inline bool operator!=(const BidiStatus &status1, const BidiStatus &status2)
 {
     return !(status1 == status2);
 }
 
 // when modifying this function, make sure you check InlineMinMaxIterator::next() as well.
 static inline RenderObject *Bidinext(RenderObject *par, RenderObject *current, BidiState *bidi = nullptr,
                                      bool skipInlines = true, bool *endOfInline = nullptr)
 {
     RenderObject *next = nullptr;
     bool oldEndOfInline = endOfInline ? *endOfInline : false;
     if (oldEndOfInline) {
         *endOfInline = false;
     }
     while (current != nullptr) {
         //qCDebug(KHTML_LOG) << "current = " << current;
         if (!oldEndOfInline && !current->isFloating() && !current->isReplaced() && !current->isPositioned()) {
             next = current->firstChild();
             if (next && bidi) {
                 EUnicodeBidi ub = next->style()->unicodeBidi();
                 if (ub != UBNormal && !emptyRun) {
                     EDirection dir = next->style()->direction();
                     QChar::Direction d = (ub == Embed ? (dir == RTL ? QChar::DirRLE : QChar::DirLRE)
                                           : (dir == RTL ? QChar::DirRLO : QChar::DirLRO));
                     embed(d, *bidi);
                 }
             }
         }
         if (!next) {
             if (!skipInlines && !oldEndOfInline && current->isInlineFlow() && endOfInline) {
                 next = current;
                 *endOfInline = true;
                 break;
             }
 
             while (current && current != par) {
                 next = current->nextSibling();
                 if (next) {
                     break;
                 }
                 if (bidi && current->style()->unicodeBidi() != UBNormal && !emptyRun) {
                     embed(QChar::DirPDF, *bidi);
                 }
                 current = current->parent();
                 if (!skipInlines && current && current != par && current->isInlineFlow() && endOfInline) {
                     next = current;
                     *endOfInline = true;
                     break;
                 }
             }
         }
 
         if (!next) {
             break;
         }
 
         if (next->isText() || next->isBR() || next->isFloating() || next->isReplaced() || next->isPositioned() || next->isGlyph()
                 || ((!skipInlines || !next->firstChild()) // Always return EMPTY inlines.
                     && next->isInlineFlow())) {
             break;
         }
         current = next;
         next    = nullptr;
     }
     return next;
 }
 
 static RenderObject *first(RenderObject *par, BidiState *bidi, bool skipInlines = true)
 {
     if (!par->firstChild()) {
         return nullptr;
     }
     RenderObject *o = par->firstChild();
 
     if (o->isInlineFlow()) {
         if (skipInlines && o->firstChild()) {
             o = Bidinext(par, o, bidi, skipInlines);
         } else {
             return o;    // Never skip empty inlines.
         }
     }
 
     if (o && !o->isText() && !o->isBR() && !o->isReplaced() && !o->isFloating() && !o->isPositioned() && !o->isGlyph()) {
         o = Bidinext(par, o, bidi, skipInlines);
     }
     return o;
 }
 
 inline void BidiIterator::increment(BidiState *bidi, bool skipInlines)
 {
     if (!obj) {
         return;
     }
     if (obj->isText()) {
         pos++;
         if (pos >= static_cast<RenderText *>(obj)->stringLength()) {
             obj = Bidinext(par, obj, bidi, skipInlines);
             pos = 0;
         }
     } else {
         obj = Bidinext(par, obj, bidi, skipInlines, &endOfInline);
         pos = 0;
     }
 }
 
 inline bool BidiIterator::atEnd() const
 {
     if (!obj) {
         return true;
     }
     return false;
 }
 
 const QChar &BidiIterator::current() const
 {
     static QChar nonBreakingSpace(0xA0);
 
     if (!obj || !obj->isText()) {
         return nonBreakingSpace;
     }
 
     RenderText *text = static_cast<RenderText *>(obj);
     if (!text->text()) {
         return nonBreakingSpace;
     }
 
     return text->text()[pos];
 }
 
 inline QChar::Direction BidiIterator::direction() const
 {
     if (!obj || !obj->isText()) {
         return QChar::DirON;
     }
 
     RenderText *renderTxt = static_cast<RenderText *>(obj);
     if (pos >= renderTxt->stringLength()) {
         return QChar::DirON;
     }
 
     return renderTxt->text()[pos].direction();
 }
 
 // -------------------------------------------------------------------------------------------------
 
 static void addRun(BidiRun *bidiRun)
 {
     if (!sFirstBidiRun) {
         sFirstBidiRun = sLastBidiRun = bidiRun;
     } else {
         sLastBidiRun->nextRun = bidiRun;
         sLastBidiRun = bidiRun;
     }
     sBidiRunCount++;
     bidiRun->compact = sBuildingCompactRuns;
 
     // Compute the number of spaces in this run,
     if (bidiRun->obj && bidiRun->obj->isText()) {
         RenderText *text = static_cast<RenderText *>(bidiRun->obj);
         if (text->text()) {
             for (int i = bidiRun->start; i < bidiRun->stop; i++) {
                 const QChar c = text->text()[i];
                 if (c.unicode() == '\n' || c.category() == QChar::Separator_Space) {
                     numSpaces++;
                 }
             }
         }
     }
 }
 
 static void reverseRuns(int start, int end)
 {
     if (start >= end) {
         return;
     }
 
     assert(start >= 0 && end < sBidiRunCount);
 
     // Get the item before the start of the runs to reverse and put it in
     // |beforeStart|.  |curr| should point to the first run to reverse.
     BidiRun *curr = sFirstBidiRun;
     BidiRun *beforeStart = nullptr;
     int i = 0;
     while (i < start) {
         i++;
         beforeStart = curr;
         curr = curr->nextRun;
     }
 
     BidiRun *startRun = curr;
     while (i < end) {
         i++;
         curr = curr->nextRun;
     }
     BidiRun *endRun = curr;
     BidiRun *afterEnd = curr->nextRun;
 
     i = start;
     curr = startRun;
     BidiRun *newNext = afterEnd;
     while (i <= end) {
         // Do the reversal.
         BidiRun *next = curr->nextRun;
         curr->nextRun = newNext;
         newNext = curr;
         curr = next;
         i++;
     }
 
     // Now hook up beforeStart and afterEnd to the newStart and newEnd.
     if (beforeStart) {
         beforeStart->nextRun = endRun;
     } else {
         sFirstBidiRun = endRun;
     }
 
     startRun->nextRun = afterEnd;
     if (!afterEnd) {
         sLastBidiRun = startRun;
     }
 }
 
 static void chopMidpointsAt(RenderObject *obj, uint pos)
 {
     if (!sNumMidpoints) {
         return;
     }
     BidiIterator *midpoints = smidpoints->data();
     for (uint i = 0; i < sNumMidpoints; i++) {
         const BidiIterator &point = midpoints[i];
         if (point.obj == obj && point.pos == pos) {
             sNumMidpoints = i;
             break;
         }
     }
 }
 
 static void checkMidpoints(BidiIterator &lBreak)
 {
     // Check to see if our last midpoint is a start point beyond the line break.  If so,
     // shave it off the list, and shave off a trailing space if the previous end point isn't
     // white-space: pre.
     if (lBreak.obj && sNumMidpoints && sNumMidpoints % 2 == 0) {
         BidiIterator *midpoints = smidpoints->data();
         BidiIterator &endpoint = midpoints[sNumMidpoints - 2];
         const BidiIterator &startpoint = midpoints[sNumMidpoints - 1];
         BidiIterator currpoint = endpoint;
         while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak) {
             currpoint.increment();
         }
         if (currpoint == lBreak) {
             // We hit the line break before the start point.  Shave off the start point.
             sNumMidpoints--;
             if (!endpoint.obj->style()->preserveWS()) {
                 if (endpoint.obj->isText()) {
                     // Don't shave a character off the endpoint if it was from a soft hyphen.
                     RenderText *textObj = static_cast<RenderText *>(endpoint.obj);
                     if (endpoint.pos + 1 < textObj->length() &&
                             textObj->text()[endpoint.pos + 1].unicode() == SOFT_HYPHEN) {
                         return;
                     }
                 }
                 endpoint.pos--;
             }
         }
     }
 }
 
 static void addMidpoint(const BidiIterator &midpoint)
 {
     if (!smidpoints) {
         return;
     }
 
     if (smidpoints->size() <= (int)sNumMidpoints) {
         smidpoints->resize(sNumMidpoints + 10);
     }
 
     BidiIterator *midpoints = smidpoints->data();
 
     // do not place midpoints in inline flows that are going to be skipped by the bidi iteration process.
     // Place them at the next non-skippable object instead.
     // #### eventually, we may want to have the same iteration in bidi and in findNextLineBreak,
     //      then this extra complexity can go away.
     if (midpoint.obj && midpoint.obj->isInlineFlow() && (midpoint.obj->firstChild() || midpoint.endOfInline)) {
         BidiIterator n = midpoint;
         n.increment();
         assert(!n.endOfInline);
         // we'll recycle the endOfInline flag to mean : don't include this stop point, stop right before it.
         // this is necessary because we just advanced our position to skip an inline, so we passed the real stop point
         n.endOfInline = true;
         if (!n.atEnd()) {
             midpoints[sNumMidpoints++] = n;
         }
     } else {
         assert(!midpoint.endOfInline);
         midpoints[sNumMidpoints++] = midpoint;
     }
 }
 
 static void appendRunsForObject(int start, int end, RenderObject *obj, BidiState &bidi)
 {
     if (start > end || obj->isFloating() ||
             (obj->isPositioned() && !obj->hasStaticX() && !obj->hasStaticY())) {
         return;
     }
 
     bool haveNextMidpoint = (smidpoints && sCurrMidpoint < sNumMidpoints);
     BidiIterator nextMidpoint;
     if (haveNextMidpoint) {
         nextMidpoint = smidpoints->at(sCurrMidpoint);
     }
     if (betweenMidpoints) {
         if (!(haveNextMidpoint && nextMidpoint.obj == obj)) {
             return;
         }
         // This is a new start point. Stop ignoring objects and
         // adjust our start.
         betweenMidpoints = false;
         start = nextMidpoint.pos;
         sCurrMidpoint++;
         if (start < end) {
             return appendRunsForObject(start, end, obj, bidi);
         }
     } else {
         if (!smidpoints || !haveNextMidpoint || (obj != nextMidpoint.obj)) {
             addRun(new(obj->renderArena()) BidiRun(start, end, obj, bidi.context, dir));
             return;
         }
 
         // An end midpoint has been encountered within our object.  We
         // need to go ahead and append a run with our endpoint.
         if (int(nextMidpoint.pos + 1) <= end) {
             betweenMidpoints = true;
             sCurrMidpoint++;
             if (nextMidpoint.pos != UINT_MAX) { // UINT_MAX means stop at the object and don't include any of it.
                 if (!nextMidpoint.endOfInline) // In this context, this flag means the stop point is exclusive, not inclusive (see addMidpoint).
                     addRun(new(obj->renderArena())
                            BidiRun(start, nextMidpoint.pos + 1, obj, bidi.context, dir));
                 return appendRunsForObject(nextMidpoint.pos + 1, end, obj, bidi);
             }
         } else {
             addRun(new(obj->renderArena()) BidiRun(start, end, obj, bidi.context, dir));
         }
     }
 }
 
 static void appendRun(BidiState &bidi)
 {
     if (emptyRun) {
         return;
     }
 #if BIDI_DEBUG > 1
     qCDebug(KHTML_LOG) << "appendRun: dir=" << (int)dir;
 #endif
 
     int start = bidi.sor.pos;
     RenderObject *obj = bidi.sor.obj;
     while (obj && obj != bidi.eor.obj) {
         appendRunsForObject(start, obj->length(), obj, bidi);
         start = 0;
         obj = Bidinext(bidi.sor.par, obj);
     }
     if (obj) {
         appendRunsForObject(start, bidi.eor.pos + 1, obj, bidi);
     }
 
     bidi.eor.increment();
     bidi.sor = bidi.eor;
     dir = QChar::DirON;
     bidi.status.eor = QChar::DirON;
 }
 
 static void embed(QChar::Direction d, BidiState &bidi)
 {
 #if BIDI_DEBUG > 1
     qDebug("*** embed dir=%d emptyrun=%d", d, emptyRun);
 #endif
     if (d == QChar::DirPDF) {
         BidiContext *c = bidi.context->parent;
         if (c) {
             if (bidi.eor != bidi.last) {
                 appendRun(bidi);
                 bidi.eor = bidi.last;
             }
             appendRun(bidi);
             emptyRun = true;
             bidi.status.last = bidi.context->dir;
             bidi.context->deref();
             bidi.context = c;
             if (bidi.context->override) {
                 dir = bidi.context->dir;
             } else {
                 dir = QChar::DirON;
             }
             bidi.status.lastStrong = bidi.context->dir;
         }
     } else {
         QChar::Direction runDir;
         if (d == QChar::DirRLE || d == QChar::DirRLO) {
             runDir = QChar::DirR;
         } else {
             runDir = QChar::DirL;
         }
         bool override;
         if (d == QChar::DirLRO || d == QChar::DirRLO) {
             override = true;
         } else {
             override = false;
         }
 
         unsigned char level = bidi.context->level;
         if (runDir == QChar::DirR) {
             if (level % 2) { // we have an odd level
                 level += 2;
             } else {
                 level++;
             }
         } else {
             if (level % 2) { // we have an odd level
                 level++;
             } else {
                 level += 2;
             }
         }
 
         if (level < 61) {
             if (bidi.eor != bidi.last) {
                 appendRun(bidi);
                 bidi.eor = bidi.last;
             }
             appendRun(bidi);
             emptyRun = true;
 
             bidi.context = new BidiContext(level, runDir, bidi.context, override);
             bidi.context->ref();
             dir = runDir;
             bidi.status.last = runDir;
             bidi.status.lastStrong = runDir;
             bidi.status.eor = runDir;
         }
     }
 }
 
 InlineFlowBox *RenderBlock::createLineBoxes(RenderObject *obj)
 {
     // See if we have an unconstructed line box for this object that is also
     // the last item on the line.
     KHTMLAssert(obj->isInlineFlow() || obj == this);
     RenderFlow *flow = static_cast<RenderFlow *>(obj);
 
     // Get the last box we made for this render object.
     InlineFlowBox *box = flow->lastLineBox();
 
     // If this box is constructed then it is from a previous line, and we need
     // to make a new box for our line.  If this box is unconstructed but it has
     // something following it on the line, then we know we have to make a new box
     // as well.  In this situation our inline has actually been split in two on
     // the same line (this can happen with very fancy language mixtures).
     if (!box || box->isConstructed() || box->nextOnLine()) {
         // We need to make a new box for this render object.  Once
         // made, we need to place it at the end of the current line.
         InlineBox *newBox = obj->createInlineBox(false, obj == this);
         KHTMLAssert(newBox->isInlineFlowBox());
         box = static_cast<InlineFlowBox *>(newBox);
         box->setFirstLineStyleBit(m_firstLine);
 
         // We have a new box. Append it to the inline box we get by constructing our
         // parent.  If we have hit the block itself, then |box| represents the root
         // inline box for the line, and it doesn't have to be appended to any parent
         // inline.
         if (obj != this) {
             InlineFlowBox *parentBox = createLineBoxes(obj->parent());
             parentBox->addToLine(box);
         }
     }
 
     return box;
 }
 
 RootInlineBox *RenderBlock::constructLine(const BidiIterator &/*start*/, const BidiIterator &end)
 {
     if (!sFirstBidiRun) {
         return nullptr;    // We had no runs. Don't make a root inline box at all. The line is empty.
     }
 
     InlineFlowBox *parentBox = nullptr;
     for (BidiRun *r = sFirstBidiRun; r; r = r->nextRun) {
         // Create a box for our object.
         r->box = r->obj->createInlineBox(r->obj->isPositioned(), false);
 
         // If we have no parent box yet, or if the run is not simply a sibling,
         // then we need to construct inline boxes as necessary to properly enclose the
         // run's inline box.
         if (!parentBox || (parentBox->object() != r->obj->parent()))
             // Create new inline boxes all the way back to the appropriate insertion point.
         {
             parentBox = createLineBoxes(r->obj->parent());
         }
 
         // Append the inline box to this line.
         parentBox->addToLine(r->box);
     }
 
     // We should have a root inline box.  It should be unconstructed and
     // be the last continuation of our line list.
     KHTMLAssert(lastLineBox() && !lastLineBox()->isConstructed());
 
     // Set bits on our inline flow boxes that indicate which sides should
     // paint borders/margins/padding.  This knowledge will ultimately be used when
     // we determine the horizontal positions and widths of all the inline boxes on
     // the line.
     RenderObject *endObject = nullptr;
     bool lastLine = !end.obj;
     if (end.obj && end.pos == 0) {
         endObject = end.obj;
     }
     lastLineBox()->determineSpacingForFlowBoxes(lastLine, endObject);
 
     // Now mark the line boxes as being constructed.
     lastLineBox()->setConstructed();
 
     // Return the last line.
     return lastRootBox();
 }
 
 void RenderBlock::computeHorizontalPositionsForLine(InlineFlowBox *lineBox, BidiState &bidi)
 {
     // First determine our total width.
     int totWidth = lineBox->getFlowSpacingWidth();
     BidiRun *r = nullptr;
     for (r = sFirstBidiRun; r; r = r->nextRun) {
         if (r->obj->isPositioned()) {
             continue;    // Positioned objects are only participating to figure out their
         }
         // correct static x position.  They have no effect on the width.
         if (r->obj->isText()) {
             r->box->setWidth(static_cast<RenderText *>(r->obj)->width(r->start, r->stop - r->start, m_firstLine));
         } else if (!r->obj->isInlineFlow()) {
             r->obj->calcWidth(); // Is this really needed or the object width is already correct here ?
             r->box->setWidth(r->obj->width());
             totWidth += r->obj->marginLeft() + r->obj->marginRight();
         }
         totWidth += r->box->width();
     }
 
     // Armed with the total width of the line (without justification),
     // we now examine our text-align property in order to determine where to position the
     // objects horizontally.  The total width of the line can be increased if we end up
     // justifying text.
     int x = leftOffset(m_height);
     int availableWidth = lineWidth(m_height);
     switch (style()->textAlign()) {
     case LEFT:
     case KHTML_LEFT:
         if (style()->direction() == RTL && totWidth > availableWidth) {
             x -= (totWidth - availableWidth);
         }
         numSpaces = 0;
         break;
     case JUSTIFY:
         if (numSpaces != 0 && !bidi.current.atEnd() && !bidi.current.obj->isBR()) {
             break;
         }
     // fall through
     case TAAUTO:
         numSpaces = 0;
         // for right to left fall through to right aligned
         if (bidi.context->basicDir == QChar::DirL) {
             break;
         }
     case RIGHT:
     case KHTML_RIGHT:
         if (style()->direction() == RTL || totWidth < availableWidth) {
             x += availableWidth - totWidth;
         }
         numSpaces = 0;
         break;
     case CENTER:
     case KHTML_CENTER:
         int xd = (availableWidth - totWidth) / 2;
         x += xd > 0 ? xd : 0;
         numSpaces = 0;
         break;
     }
 
     if (numSpaces > 0) {
         for (r = sFirstBidiRun; r; r = r->nextRun) {
             int spaceAdd = 0;
             if (numSpaces > 0 && r->obj->isText()) {
                 // get the number of spaces in the run
                 int spaces = 0;
                 for (int i = r->start; i < r->stop; i++) {
                     const QChar c = static_cast<RenderText *>(r->obj)->text()[i];
                     if (c.category() == QChar::Separator_Space || c == '\n') {
                         spaces++;
                     }
                 }
 
                 KHTMLAssert(spaces <= numSpaces);
 
                 // Only justify text with white-space: normal.
                 if (r->obj->style()->whiteSpace() == NORMAL) {
                     spaceAdd = (availableWidth - totWidth) * spaces / numSpaces;
                     spaceAdd = qMax(0, spaceAdd);
                     static_cast<InlineTextBox *>(r->box)->setSpaceAdd(spaceAdd);
                     totWidth += spaceAdd;
                 }
                 numSpaces -= spaces;
             }
         }
     }
 
     // The widths of all runs are now known.  We can now place every inline box (and
     // compute accurate widths for the inline flow boxes).
     int rightPos = lineBox->placeBoxesHorizontally(x);
     if (rightPos > m_overflowWidth) {
         m_overflowWidth = rightPos;    // FIXME: Work for rtl overflow also.
     }
     if (x < 0) {
         m_overflowLeft = qMin(m_overflowLeft, x);
     }
 }
 
 void RenderBlock::computeVerticalPositionsForLine(RootInlineBox *lineBox)
 {
     lineBox->verticallyAlignBoxes(m_height);
     lineBox->setBlockHeight(m_height);
 
     // Check for page-breaks
     if (canvas()->pagedMode() && !lineBox->afterPageBreak())
         // If we get a page-break we might need to redo the line-break
         if (clearLineOfPageBreaks(lineBox) && hasFloats()) {
             return;
         }
 
     // See if the line spilled out.  If so set overflow height accordingly.
     int bottomOfLine = lineBox->bottomOverflow();
     if (bottomOfLine > m_height && bottomOfLine > m_overflowHeight) {
         m_overflowHeight = bottomOfLine;
     }
 
     bool beforeContent = true;
 
     // Now make sure we place replaced render objects correctly.
     for (BidiRun *r = sFirstBidiRun; r; r = r->nextRun) {
 
         // For positioned placeholders, cache the static Y position an object with non-inline display would have.
         // Either it is unchanged if it comes before any real linebox, or it must clear the current line (already accounted in m_height).
         // This value will be picked up by position() if relevant.
         if (r->obj->isPositioned()) {
             r->box->setYPos(beforeContent && r->obj->isBox() ? static_cast<RenderBox *>(r->obj)->staticY() : m_height);
         } else if (beforeContent) {
             beforeContent = false;
         }
 
         // Position is used to properly position both replaced elements and
         // to update the static normal flow x/y of positioned elements.
         r->obj->position(r->box, r->start, r->stop - r->start, r->level % 2);
     }
 }
 
 bool RenderBlock::clearLineOfPageBreaks(InlineFlowBox *lineBox)
 {
     bool doPageBreak = false;
     // Check for physical page-breaks
     int xpage = crossesPageBreak(lineBox->topOverflow(), lineBox->bottomOverflow());
     if (xpage) {
 #ifdef PAGE_DEBUG
         qCDebug(KHTML_LOG) << renderName() << " Line crosses to page " << xpage;
         qCDebug(KHTML_LOG) << renderName() << " at pos " << lineBox->yPos() << " height " << lineBox->height();
 #endif
 
         doPageBreak = true;
         // check page-break-inside
         if (!style()->pageBreakInside()) {
             if (parent()->canClear(this, PageBreakNormal)) {
                 setNeedsPageClear(true);
                 doPageBreak = false;
             }
 #ifdef PAGE_DEBUG
             else {
                 qCDebug(KHTML_LOG) << "Ignoring page-break-inside: avoid";
             }
 #endif
         }
         // check orphans
         int orphans = 0;
         InlineRunBox *box = lineBox->prevLineBox();
         while (box && orphans < style()->orphans()) {
             orphans++;
             box = box->prevLineBox();
         }
 
         if (orphans == 0) {
             setNeedsPageClear(true);
             doPageBreak = false;
         } else if (orphans < style()->orphans()) {
 #ifdef PAGE_DEBUG
             qCDebug(KHTML_LOG) << "Orphans: " << orphans;
 #endif
             // Orphans is a level 2 page-break rule and can be broken only
             // if the break is physically required.
             if (parent()->canClear(this, PageBreakHarder)) {
                 // move block instead
                 setNeedsPageClear(true);
                 doPageBreak = false;
             }
 #ifdef PAGE_DEBUG
             else {
                 qCDebug(KHTML_LOG) << "Ignoring violated orphans";
             }
 #endif
         }
         if (doPageBreak) {
 #ifdef PAGE_DEBUG
             int oldYPos = lineBox->yPos();
 #endif
             int pTop = pageTopAfter(lineBox->yPos());
             m_height = pTop;
             lineBox->setAfterPageBreak(true);
             lineBox->verticallyAlignBoxes(m_height);
             if (lineBox->yPos() < pTop) {
                 // ### serious crap. render_line is sometimes placing lines too high
                 // qCDebug(KHTML_LOG) << "page top overflow by repositioned line";
                 int heightIncrease = pTop - lineBox->yPos();
                 m_height = pTop + heightIncrease;
                 lineBox->verticallyAlignBoxes(m_height);
             }
 #ifdef PAGE_DEBUG
             qCDebug(KHTML_LOG) << "Cleared line " << lineBox->yPos() - oldYPos << "px";
 #endif
             setContainsPageBreak(true);
         }
     }
     return doPageBreak;
 }
 
 // collects one line of the paragraph and transforms it to visual order
 void RenderBlock::bidiReorderLine(const BidiIterator &start, const BidiIterator &end, BidiState &bidi)
 {
     if (start == end) {
         if (start.current() == '\n') {
             m_height += lineHeight(m_firstLine);
         }
         return;
     }
 
 #if BIDI_DEBUG > 1
     qCDebug(KHTML_LOG) << "reordering Line from " << start.obj << "/" << start.pos << " to " << end.obj << "/" << end.pos;
 #endif
 
     sFirstBidiRun = nullptr;
     sLastBidiRun = nullptr;
     sBidiRunCount = 0;
 
     //    context->ref();
 
     dir = QChar::DirON;
     emptyRun = true;
 
     numSpaces = 0;
 
     bidi.current = start;
     bidi.last = bidi.current;
     bool atEnd = false;
     while (1) {
         QChar::Direction dirCurrent;
         if (atEnd) {
             //qCDebug(KHTML_LOG) << "atEnd";
             BidiContext *c = bidi.context;
             if (bidi.current.atEnd())
                 while (c->parent) {
                     c = c->parent;
                 }
             dirCurrent = c->dir;
         } else if (bidi.context->override) {
             dirCurrent = bidi.context->dir;
         } else {
             dirCurrent = bidi.current.direction();
         }
 
 #ifndef QT_NO_UNICODETABLES
 
 #if BIDI_DEBUG > 1
         qCDebug(KHTML_LOG) << "directions: dir=" << (int)dir << " current=" << (int)dirCurrent << " last=" << bidi.status.last << " eor=" << bidi.status.eor << " lastStrong=" << bidi.status.lastStrong << " embedding=" << (int)bidi.context->dir << " level =" << (int)bidi.context->level;
 #endif
 
         switch (dirCurrent) {
 
         // embedding and overrides (X1-X9 in the Bidi specs)
         case QChar::DirRLE:
         case QChar::DirLRE:
         case QChar::DirRLO:
         case QChar::DirLRO:
         case QChar::DirPDF:
             embed(dirCurrent, bidi);
             break;
 
         // strong types
         case QChar::DirL:
             if (dir == QChar::DirON) {
                 dir = QChar::DirL;
             }
             switch (bidi.status.last) {
             case QChar::DirL:
                 bidi.eor = bidi.current; bidi.status.eor = QChar::DirL; break;
             case QChar::DirR:
             case QChar::DirAL:
             case QChar::DirEN:
             case QChar::DirAN:
                 appendRun(bidi);
                 break;
             case QChar::DirES:
             case QChar::DirET:
             case QChar::DirCS:
             case QChar::DirBN:
             case QChar::DirB:
             case QChar::DirS:
             case QChar::DirWS:
             case QChar::DirON:
                 if (bidi.status.eor != QChar::DirL) {
                     //last stuff takes embedding dir
                     if (bidi.context->dir == QChar::DirL || bidi.status.lastStrong == QChar::DirL) {
                         if (bidi.status.eor != QChar::DirEN && bidi.status.eor != QChar::DirAN && bidi.status.eor != QChar::DirON) {
                             appendRun(bidi);
                         }
                         dir = QChar::DirL;
                         bidi.eor = bidi.current;
                         bidi.status.eor = QChar::DirL;
                     } else {
                         if (bidi.status.eor == QChar::DirEN || bidi.status.eor == QChar::DirAN) {
                             dir = bidi.status.eor;
                             appendRun(bidi);
                         }
                         dir = QChar::DirR;
                         bidi.eor = bidi.last;
                         appendRun(bidi);
                         dir = QChar::DirL;
                         bidi.status.eor = QChar::DirL;
                     }
                 } else {
                     bidi.eor = bidi.current; bidi.status.eor = QChar::DirL;
                 }
             default:
                 break;
             }
             bidi.status.lastStrong = QChar::DirL;
             break;
         case QChar::DirAL:
         case QChar::DirR:
             if (dir == QChar::DirON) {
                 dir = QChar::DirR;
             }
             switch (bidi.status.last) {
             case QChar::DirR:
             case QChar::DirAL:
                 bidi.eor = bidi.current; bidi.status.eor = QChar::DirR; break;
             case QChar::DirL:
             case QChar::DirEN:
             case QChar::DirAN:
                 appendRun(bidi);
                 dir = QChar::DirR;
                 bidi.eor = bidi.current;
                 bidi.status.eor = QChar::DirR;
                 break;
             case QChar::DirES:
             case QChar::DirET:
             case QChar::DirCS:
             case QChar::DirBN:
             case QChar::DirB:
             case QChar::DirS:
             case QChar::DirWS:
             case QChar::DirON:
                 if (!(bidi.status.eor == QChar::DirR) && !(bidi.status.eor == QChar::DirAL)) {
                     //last stuff takes embedding dir
                     if (bidi.context->dir == QChar::DirR || bidi.status.lastStrong == QChar::DirR
                             || bidi.status.lastStrong == QChar::DirAL) {
                         appendRun(bidi);
                         dir = QChar::DirR;
                         bidi.eor = bidi.current;
                         bidi.status.eor = QChar::DirR;
                     } else {
                         dir = QChar::DirL;
                         bidi.eor = bidi.last;
                         appendRun(bidi);
                         dir = QChar::DirR;
                         bidi.status.eor = QChar::DirR;
                     }
                 } else {
                     bidi.eor = bidi.current; bidi.status.eor = QChar::DirR;
                 }
             default:
                 break;
             }
             bidi.status.lastStrong = dirCurrent;
             break;
 
         // weak types:
 
         case QChar::DirNSM:
             // ### if @sor, set dir to dirSor
             break;
         case QChar::DirEN:
             if (!(bidi.status.lastStrong == QChar::DirAL)) {
                 // if last strong was AL change EN to AN
                 if (dir == QChar::DirON) {
                     dir = QChar::DirL;
                 }
                 switch (bidi.status.last) {
                 case QChar::DirET:
                     if (bidi.status.lastStrong == QChar::DirR || bidi.status.lastStrong == QChar::DirAL) {
                         appendRun(bidi);
                         dir = QChar::DirEN;
                         bidi.status.eor = QChar::DirEN;
                     }
                 // fall through
                 case QChar::DirEN:
                 case QChar::DirL:
                     bidi.eor = bidi.current;
                     bidi.status.eor = dirCurrent;
                     break;
                 case QChar::DirR:
                 case QChar::DirAL:
                 case QChar::DirAN:
                     appendRun(bidi);
                     bidi.status.eor = QChar::DirEN;
                     dir = QChar::DirEN; break;
                 case QChar::DirES:
                 case QChar::DirCS:
                     if (bidi.status.eor == QChar::DirEN) {
                         bidi.eor = bidi.current; break;
                     }
                 case QChar::DirBN:
                 case QChar::DirB:
                 case QChar::DirS:
                 case QChar::DirWS:
                 case QChar::DirON:
                     if (bidi.status.eor == QChar::DirR) {
                         // neutrals go to R
                         bidi.eor = bidi.last;
                         appendRun(bidi);
                         dir = QChar::DirEN;
                         bidi.status.eor = QChar::DirEN;
                     } else if (bidi.status.eor == QChar::DirL ||
                                (bidi.status.eor == QChar::DirEN && bidi.status.lastStrong == QChar::DirL)) {
                         bidi.eor = bidi.current; bidi.status.eor = dirCurrent;
                     } else {
                         // numbers on both sides, neutrals get right to left direction
                         if (dir != QChar::DirL) {
                             appendRun(bidi);
                             bidi.eor = bidi.last;
                             dir = QChar::DirR;
                             appendRun(bidi);
                             dir = QChar::DirEN;
                             bidi.status.eor = QChar::DirEN;
                         } else {
                             bidi.eor = bidi.current; bidi.status.eor = dirCurrent;
                         }
                     }
                 default:
                     break;
                 }
                 break;
             }
         case QChar::DirAN:
             dirCurrent = QChar::DirAN;
             if (dir == QChar::DirON) {
                 dir = QChar::DirAN;
             }
             switch (bidi.status.last) {
             case QChar::DirL:
             case QChar::DirAN:
                 bidi.eor = bidi.current; bidi.status.eor = QChar::DirAN; break;
             case QChar::DirR:
             case QChar::DirAL:
             case QChar::DirEN:
                 appendRun(bidi);
                 dir = QChar::DirAN; bidi.status.eor = QChar::DirAN;
                 break;
             case QChar::DirCS:
                 if (bidi.status.eor == QChar::DirAN) {
                     bidi.eor = bidi.current; break;
                 }
             case QChar::DirES:
             case QChar::DirET:
             case QChar::DirBN:
             case QChar::DirB:
             case QChar::DirS:
             case QChar::DirWS:
             case QChar::DirON:
                 if (bidi.status.eor == QChar::DirR) {
                     // neutrals go to R
                     bidi.eor = bidi.last;
                     appendRun(bidi);
                     dir = QChar::DirAN;
                     bidi.status.eor = QChar::DirAN;
                 } else if (bidi.status.eor == QChar::DirL ||
                            (bidi.status.eor == QChar::DirEN && bidi.status.lastStrong == QChar::DirL)) {
                     bidi.eor = bidi.current; bidi.status.eor = dirCurrent;
                 } else {
                     // numbers on both sides, neutrals get right to left direction
                     if (dir != QChar::DirL) {
                         appendRun(bidi);
                         bidi.eor = bidi.last;
                         dir = QChar::DirR;
                         appendRun(bidi);
                         dir = QChar::DirAN;
                         bidi.status.eor = QChar::DirAN;
                     } else {
                         bidi.eor = bidi.current; bidi.status.eor = dirCurrent;
                     }
                 }
             default:
                 break;
             }
             break;
         case QChar::DirES:
         case QChar::DirCS:
             break;
         case QChar::DirET:
             if (bidi.status.last == QChar::DirEN) {
                 dirCurrent = QChar::DirEN;
                 bidi.eor = bidi.current; bidi.status.eor = dirCurrent;
                 break;
             }
             break;
 
         // boundary neutrals should be ignored
         case QChar::DirBN:
             break;
         // neutrals
         case QChar::DirB:
             // ### what do we do with newline and paragraph separators that come to here?
             break;
         case QChar::DirS:
             // ### implement rule L1
             break;
         case QChar::DirWS:
             break;
         case QChar::DirON:
             break;
         default:
             break;
         }
 
         //cout << "     after: dir=" << //        dir << " current=" << dirCurrent << " last=" << status.last << " eor=" << status.eor << " lastStrong=" << status.lastStrong << " embedding=" << context->dir << endl;
 
         if (bidi.current.atEnd()) {
             break;
         }
 
         // set status.last as needed.
         switch (dirCurrent) {
         case QChar::DirET:
         case QChar::DirES:
         case QChar::DirCS:
         case QChar::DirS:
         case QChar::DirWS:
         case QChar::DirON:
             switch (bidi.status.last) {
             case QChar::DirL:
             case QChar::DirR:
             case QChar::DirAL:
             case QChar::DirEN:
             case QChar::DirAN:
                 bidi.status.last = dirCurrent;
                 break;
             default:
                 bidi.status.last = QChar::DirON;
             }
             break;
         case QChar::DirNSM:
         case QChar::DirBN:
             // ignore these
             break;
         case QChar::DirEN:
             if (bidi.status.last == QChar::DirL) {
                 break;
             }
         // fall through
         default:
             bidi.status.last = dirCurrent;
         }
 #endif
 
         if (atEnd) {
             break;
         }
         bidi.last = bidi.current;
 
         if (emptyRun) {
             bidi.sor = bidi.current;
             bidi.eor = bidi.current;
             emptyRun = false;
         }
 
         // this causes the operator ++ to open and close embedding levels as needed
         // for the CSS unicode-bidi property
         bidi.current.increment(&bidi);
 
         if (bidi.current == end) {
             if (emptyRun) {
                 break;
             }
             atEnd = true;
         }
     }
 
 #if BIDI_DEBUG > 0
     qCDebug(KHTML_LOG) << "reached end of line current=" << bidi.current.obj << "/" << bidi.current.pos
              << ", eor=" << bidi.eor.obj << "/" << bidi.eor.pos;
 #endif
     if (!emptyRun && bidi.sor != bidi.current) {
         bidi.eor = bidi.last;
         appendRun(bidi);
     }
 
     // reorder line according to run structure...
 
     // first find highest and lowest levels
     uchar levelLow = 128;
     uchar levelHigh = 0;
     BidiRun *r = sFirstBidiRun;
     while (r) {
         if (r->level > levelHigh) {
             levelHigh = r->level;
         }
         if (r->level < levelLow) {
             levelLow = r->level;
         }
         r = r->nextRun;
     }
 
     // implements reordering of the line (L2 according to Bidi spec):
     // L2. From the highest level found in the text to the lowest odd level on each line,
     // reverse any contiguous sequence of characters that are at that level or higher.
 
     // reversing is only done up to the lowest odd level
     if (!(levelLow % 2)) {
         levelLow++;
     }
 
     int count = sBidiRunCount - 1;
 
     // do not reverse for visually ordered web sites
     if (!style()->visuallyOrdered()) {
         while (levelHigh >= levelLow) {
             int i = 0;
             BidiRun *currRun = sFirstBidiRun;
             while (i < count) {
                 while (i < count && currRun && currRun->level < levelHigh) {
                     i++;
                     currRun = currRun->nextRun;
                 }
                 int start = i;
                 while (i <= count && currRun && currRun->level >= levelHigh) {
                     i++;
                     currRun = currRun->nextRun;
                 }
                 int end = i - 1;
                 reverseRuns(start, end);
             }
             levelHigh--;
         }
     }
 
 #if BIDI_DEBUG > 0
     qCDebug(KHTML_LOG) << "visual order is:";
     for (BidiRun *curr = sFirstBidiRun; curr; curr = curr->nextRun) {
         qCDebug(KHTML_LOG) << "    " << curr;
     }
 #endif
 }
 
 void RenderBlock::layoutInlineChildren(bool relayoutChildren, int breakBeforeLine)
 {
     BidiState bidi;
 
     m_overflowHeight = 0;
 
     invalidateVerticalPosition();
 #ifdef DEBUG_LAYOUT
     QTime qt;
     qt.start();
     qCDebug(KHTML_LOG) << renderName() << " layoutInlineChildren( " << this << " )";
 #endif
 #if BIDI_DEBUG > 1 || defined( DEBUG_LINEBREAKS )
     qCDebug(KHTML_LOG) << " ------- bidi start " << this << " -------";
 #endif
 
     m_height = borderTop() + paddingTop();
     int toAdd = borderBottom() + paddingBottom();
     if (m_layer && scrollsOverflowX() && style()->height().isAuto()) {
         toAdd += m_layer->horizontalScrollbarHeight();
     }
 
     // Figure out if we should clear our line boxes.
     bool fullLayout = !firstLineBox() || !firstChild() || selfNeedsLayout() || relayoutChildren || hasFloats();
 
     if (fullLayout) {
         deleteInlineBoxes();
     }
 
     // Text truncation only kicks in if your overflow isn't visible and your
     // text-overflow-mode isn't clip.
     bool hasTextOverflow = style()->textOverflow() && hasOverflowClip();
 
     // Walk all the lines and delete our ellipsis line boxes if they exist.
     if (hasTextOverflow) {
         deleteEllipsisLineBoxes();
     }
 
     if (firstChild()) {
         // layout replaced elements
         RenderObject *o = first(this, nullptr, false);
         while (o) {
             invalidateVerticalPosition();
             if (!fullLayout && o->markedForRepaint()) {
                 o->repaintDuringLayout();
                 o->setMarkedForRepaint(false);
             }
             if (o->isReplaced() || o->isFloating() || o->isPositioned()) {
 
                 if ((!o->isPositioned() || o->isPosWithStaticDim()) &&
                         (relayoutChildren || o->style()->width().isPercent() || o->style()->height().isPercent())) {
                     o->setChildNeedsLayout(true, false);
                 }
 
                 if (o->isPositioned()) {
                     if (!o->inPosObjectList()) {
                         o->containingBlock()->insertPositionedObject(o);
                     }
                     if (fullLayout) {
                         static_cast<RenderBox *>(o)->RenderBox::deleteInlineBoxes();
                     }
                 } else {
                     if (fullLayout || o->needsLayout()) {
                         static_cast<RenderBox *>(o)->RenderBox::dirtyInlineBoxes(fullLayout);
                     }
                     o->layoutIfNeeded();
                 }
             } else {
                 if (fullLayout || o->selfNeedsLayout()) {
                     o->dirtyInlineBoxes(fullLayout);
                     o->setMarkedForRepaint(false);
                 }
                 o->setNeedsLayout(false);
             }
             o = Bidinext(this, o, nullptr, false);
         }
 
         BidiContext *startEmbed;
         if (style()->direction() == LTR) {
             startEmbed = new BidiContext(0, QChar::DirL);
             bidi.status.eor = QChar::DirL;
         } else {
             startEmbed = new BidiContext(1, QChar::DirR);
             bidi.status.eor = QChar::DirR;
         }
         startEmbed->ref();
 
         bidi.status.lastStrong = QChar::DirON;
         bidi.status.last = QChar::DirON;
 
         bidi.context = startEmbed;
 
         // We want to skip ahead to the first dirty line
         BidiIterator start;
         RootInlineBox *startLine = determineStartPosition(fullLayout, start, bidi);
 
         // Then look forward to see if we can find a clean area that is clean up to the end.
         BidiIterator cleanLineStart;
         BidiStatus cleanLineBidiStatus;
         BidiContext *cleanLineBidiContext = nullptr;
         int endLineYPos = 0;
         RootInlineBox *endLine = (fullLayout || !startLine) ?
                                  nullptr : determineEndPosition(startLine, cleanLineStart, cleanLineBidiStatus, cleanLineBidiContext, endLineYPos);
 
         // Extract the clean area. We will add it back if we determine that we're able to
         // synchronize after relayouting the dirty area.
         if (endLine)
             for (RootInlineBox *line = endLine; line; line = line->nextRootBox()) {
                 line->extractLine();
             }
 
         // Delete the dirty area.
         if (startLine) {
             RenderArena *arena = renderArena();
             RootInlineBox *box = startLine;
             while (box) {
                 RootInlineBox *next = box->nextRootBox();
                 box->deleteLine(arena);
                 box = next;
             }
             startLine = nullptr;
         }
         BidiIterator end = start;
         bool endLineMatched = false;
         m_firstLine = true;
 
         if (!smidpoints) {
             smidpoints = new QVector<BidiIterator>;
         }
 
         sNumMidpoints = 0;
         sCurrMidpoint = 0;
         sCompactFirstBidiRun = sCompactLastBidiRun = nullptr;
         sCompactBidiRunCount = 0;
 
         previousLineBrokeAtBR = true;
 
         int lineCount = 0;
         bool pagebreakHint = false;
         int oldPos = 0;
         BidiIterator oldStart;
         BidiState oldBidi;
         const bool pagedMode = canvas()->pagedMode();
 
         while (!end.atEnd()) {
             start = end;
             if (endLine && (endLineMatched = matchedEndLine(start, bidi.status, bidi.context, cleanLineStart, cleanLineBidiStatus, cleanLineBidiContext, endLine, endLineYPos))) {
                 break;
             }
             lineCount++;
             betweenMidpoints = false;
             isLineEmpty = true;
             pagebreakHint = false;
             if (pagedMode) {
                 oldPos = m_height;
                 oldStart = start;
                 oldBidi = bidi;
             }
             if (lineCount == breakBeforeLine) {
                 m_height = pageTopAfter(oldPos);
                 pagebreakHint = true;
             }
         redo_linebreak:
             end = findNextLineBreak(start, bidi);
             if (start.atEnd()) {
                 deleteBidiRuns(renderArena());
                 break;
             }
             if (!isLineEmpty) {
                 bidiReorderLine(start, end, bidi);
 
                 // Now that the runs have been ordered, we create the line boxes.
                 // At the same time we figure out where border/padding/margin should be applied for
                 // inline flow boxes.
 
                 RootInlineBox *lineBox = nullptr;
                 if (sBidiRunCount) {
                     lineBox = constructLine(start, end);
                     if (lineBox) {
                         lineBox->setEndsWithBreak(previousLineBrokeAtBR);
                         if (pagebreakHint) {
                             lineBox->setAfterPageBreak(true);
                         }
 
                         // Now we position all of our text runs horizontally.
                         computeHorizontalPositionsForLine(lineBox, bidi);
 
                         // Now position our text runs vertically.
                         computeVerticalPositionsForLine(lineBox);
 
                         // SVG
                         if (lineBox->isSVGRootInlineBox()) {
                             //qCDebug(KHTML_LOG) << "svgrootinline box:";
                             WebCore::SVGRootInlineBox *svgLineBox = static_cast<WebCore::SVGRootInlineBox *>(lineBox);
                             svgLineBox->computePerCharacterLayoutInformation();
                         }
 
                         deleteBidiRuns(renderArena());
 
                         if (lineBox->afterPageBreak() && hasFloats() && !pagebreakHint) {
                             start = end = oldStart;
                             bidi = oldBidi;
                             m_height = pageTopAfter(oldPos);
                             deleteLastLineBox(renderArena());
                             pagebreakHint = true;
                             goto redo_linebreak;
                         }
                     }
                 }
 
                 if (end == start || (end.obj && end.obj->isBR() && !start.obj->isBR())) {
                     end.increment(&bidi);
                 } else if (end.obj && end.obj->style()->preserveLF() && end.current() == QChar('\n')) {
                     end.increment(&bidi);
                 }
 
                 if (lineBox) {
                     lineBox->setLineBreakInfo(end.obj, end.pos, bidi.status, bidi.context);
                 }
 
                 m_firstLine = false;
                 newLine();
             }
 
             sNumMidpoints = 0;
             sCurrMidpoint = 0;
             sCompactFirstBidiRun = sCompactLastBidiRun = nullptr;
             sCompactBidiRunCount = 0;
         }
         startEmbed->deref();
         //embed->deref();
 
         if (endLine) {
             if (endLineMatched) {
                 // Attach all the remaining lines, and then adjust their y-positions as needed.
                 for (RootInlineBox *line = endLine; line; line = line->nextRootBox()) {
                     line->attachLine();
                 }
 
                 // Now apply the offset to each line if needed.
                 int delta = m_height - endLineYPos;
                 if (delta) {
                     for (RootInlineBox *line = endLine; line; line = line->nextRootBox()) {
                         line->adjustPosition(0, delta);
                     }
                 }
                 m_height = lastRootBox()->blockHeight();
             } else {
                 // Delete all the remaining lines.
                 InlineRunBox *line = endLine;
                 RenderArena *arena = renderArena();
                 while (line) {
                     InlineRunBox *next = line->nextLineBox();
                     line->deleteLine(arena);
                     line = next;
                 }
             }
         }
     }
 
     sNumMidpoints = 0;
     sCurrMidpoint = 0;
 
     // If we violate widows page-breaking rules, we set a hint and relayout.
     // Note that the widows rule might still be violated afterwards if the lines have become wider
     if (canvas()->pagedMode() && containsPageBreak() && breakBeforeLine == 0) {
         int orphans = 0;
         int widows = 0;
         // find breaking line
         InlineRunBox *lineBox = firstLineBox();
         while (lineBox) {
             if (lineBox->isInlineFlowBox()) {
                 InlineFlowBox *flowBox = static_cast<InlineFlowBox *>(lineBox);
                 if (flowBox->afterPageBreak()) {
                     break;
                 }
             }
             orphans++;
             lineBox = lineBox->nextLineBox();
         }
         InlineFlowBox *pageBreaker = static_cast<InlineFlowBox *>(lineBox);
         if (!pageBreaker) {
             goto no_break;
         }
         // count widows
         while (lineBox && widows < style()->widows()) {
             if (lineBox->hasTextChildren()) {
                 widows++;
             }
             lineBox = lineBox->nextLineBox();
         }
         // Widows rule broken and more orphans left to use
         if (widows < style()->widows() && orphans > 0) {
             // qCDebug(KHTML_LOG) << "Widows: " << widows;
             // Check if we have enough orphans after respecting widows count
             int newOrphans = orphans - (style()->widows() - widows);
             if (newOrphans < style()->orphans()) {
                 if (parent()->canClear(this, PageBreakHarder)) {
                     // Relayout to remove incorrect page-break
                     setNeedsPageClear(true);
                     setContainsPageBreak(false);
                     layoutInlineChildren(relayoutChildren, -1);
                     return;
                 }
             } else {
                 // Set hint and try again
                 layoutInlineChildren(relayoutChildren, newOrphans + 1);
                 return;
             }
         }
     }
 no_break:
 
     // in case we have a float on the last line, it might not be positioned up to now.
     // This has to be done before adding in the bottom border/padding, or the float will
     // include the padding incorrectly. -dwh
     positionNewFloats();
 
     // Now add in the bottom border/padding.
     m_height += toAdd;
 
     // Always make sure this is at least our height.
     m_overflowHeight = qMax(m_height, m_overflowHeight);
 
     // See if any lines spill out of the block.  If so, we need to update our overflow width.
     checkLinesForOverflow();
 
     // See if we have any lines that spill out of our block.  If we do, then we will
     // possibly need to truncate text.
     if (hasTextOverflow) {
         checkLinesForTextOverflow();
     }
 
 #if BIDI_DEBUG > 1
     qCDebug(KHTML_LOG) << " ------- bidi end " << this << " -------";
 #endif
     //qCDebug(KHTML_LOG) << "RenderBlock::layoutInlineChildren time used " << qt.elapsed();
     //qCDebug(KHTML_LOG) << "height = " << m_height;
 }
 
 RootInlineBox *RenderBlock::determineStartPosition(bool fullLayout, BidiIterator &start, BidiState &bidi)
 {
     RootInlineBox *curr = nullptr;
     RootInlineBox *last = nullptr;
     RenderObject *startObj = nullptr;
     int pos = 0;
 
     if (fullLayout) {
         // Nuke all our lines.
         // ### should be done already at this point... assert( !firstRootBox() )
         if (firstRootBox()) {
             RenderArena *arena = renderArena();
             curr = firstRootBox();
             while (curr) {
                 RootInlineBox *next = curr->nextRootBox();
                 curr->deleteLine(arena);
                 curr = next;
             }
             assert(!firstLineBox() && !lastLineBox());
         }
     } else {
         int cnt = 0;
         for (curr = firstRootBox(); curr && !curr->isDirty(); curr = curr->nextRootBox()) {
             cnt++;
         }
         if (curr) {
             // qCDebug(KHTML_LOG) << "found dirty line at " << cnt;
             // We have a dirty line.
             if (RootInlineBox *prevRootBox = curr->prevRootBox()) {
                 // We have a previous line.
                 if (!prevRootBox->endsWithBreak() || (prevRootBox->lineBreakObj()->isText() && prevRootBox->lineBreakPos() >= static_cast<RenderText *>(prevRootBox->lineBreakObj())->stringLength()))
                     // The previous line didn't break cleanly or broke at a newline
                     // that has been deleted, so treat it as dirty too.
                 {
                     curr = prevRootBox;
                 }
             }
         } else {
             // qCDebug(KHTML_LOG) << "No dirty line found";
             // No dirty lines were found.
             // If the last line didn't break cleanly, treat it as dirty.
             if (lastRootBox() && !lastRootBox()->endsWithBreak()) {
                 curr = lastRootBox();
             }
         }
 
         // If we have no dirty lines, then last is just the last root box.
         last = curr ? curr->prevRootBox() : lastRootBox();
     }
 
     m_firstLine = !last;
     previousLineBrokeAtBR = !last || last->endsWithBreak();
     if (last) {
         m_height = last->blockHeight();
         startObj = last->lineBreakObj();
         pos = last->lineBreakPos();
         bidi.status = last->lineBreakBidiStatus();
     } else {
         startObj = first(this, &bidi, false);
     }
 
     start = BidiIterator(this, startObj, pos);
 
     return curr;
 }
 
 RootInlineBox *RenderBlock::determineEndPosition(RootInlineBox *startLine, BidiIterator &cleanLineStart, BidiStatus &cleanLineBidiStatus, BidiContext *cleanLineBidiContext, int &yPos)
 {
     RootInlineBox *last = nullptr;
     if (!startLine) {
         last = nullptr;
     } else {
         for (RootInlineBox *curr = startLine->nextRootBox(); curr; curr = curr->nextRootBox()) {
             if (curr->isDirty()) {
                 last = nullptr;
             } else if (!last) {
                 last = curr;
             }
         }
     }
 
     if (!last) {
         return nullptr;
     }
 
     RootInlineBox *prev = last->prevRootBox();
     cleanLineStart = BidiIterator(this, prev->lineBreakObj(), prev->lineBreakPos());
     cleanLineBidiStatus = prev->lineBreakBidiStatus();
     cleanLineBidiContext = prev->lineBreakBidiContext();
     yPos = prev->blockHeight();
 
     return last;
 }
 
 bool RenderBlock::matchedEndLine(const BidiIterator &start, const BidiStatus &status, BidiContext *context,
                                  const BidiIterator &endLineStart, const BidiStatus &endLineStatus, BidiContext *endLineContext,
                                  RootInlineBox *&endLine, int &endYPos)
 {
     if (start == endLineStart) {
         return status == endLineStatus && endLineContext && (*context == *endLineContext);
     } else {
         // The first clean line doesn't match, but we can check a handful of following lines to try
         // to match back up.
         static int numLines = 8; // The # of lines we're willing to match against.
         RootInlineBox *line = endLine;
         for (int i = 0; i < numLines && line; i++, line = line->nextRootBox()) {
             if (line->lineBreakObj() == start.obj && line->lineBreakPos() == start.pos) {
                 // We have a match.
                 if ((line->lineBreakBidiStatus() != status) || (line->lineBreakBidiContext() != context)) {
                     return false;    // ...but the bidi state doesn't match.
                 }
                 RootInlineBox *result = line->nextRootBox();
 
                 // Set our yPos to be the block height of endLine.
                 if (result) {
                     endYPos = line->blockHeight();
                 }
 
                 // Now delete the lines that we failed to sync.
                 RootInlineBox *boxToDelete = endLine;
                 RenderArena *arena = renderArena();
                 while (boxToDelete && boxToDelete != result) {
                     RootInlineBox *next = boxToDelete->nextRootBox();
                     boxToDelete->deleteLine(arena);
                     boxToDelete = next;
                 }
 
                 endLine = result;
                 return result;
             }
         }
     }
     return false;
 }
 
 static void setStaticPosition(RenderBlock *p, RenderObject *o, bool *needToSetStaticX = nullptr, bool *needToSetStaticY = nullptr)
 {
     // If our original display wasn't an inline type, then we can
     // determine our static x position now.
     bool nssx, nssy;
     bool isInlineType = o->style()->isOriginalDisplayInlineType();
     nssx = o->hasStaticX();
     if (nssx && o->isBox()) {
         static_cast<RenderBox *>(o)->setStaticX(o->parent()->style()->direction() == LTR ?
                                                 p->borderLeft() + p->paddingLeft() :
                                                 p->borderRight() + p->paddingRight());
         nssx = isInlineType;
     }
 
     // If our original display was an INLINE type, then we can
     // determine our static y position now.
     nssy = o->hasStaticY();
     if (nssy && o->isBox()) {
         static_cast<RenderBox *>(o)->setStaticY(p->height());
         nssy = !isInlineType;
     }
     if (needToSetStaticX) {
         *needToSetStaticX = nssx;
     }
     if (needToSetStaticY) {
         *needToSetStaticY = nssy;
     }
 }
 
 static inline bool requiresLineBox(BidiIterator &it)
 {
     if (it.obj->isFloatingOrPositioned()) {
         return false;
     }
     if (it.obj->isInlineFlow()) {
         return (getBorderPaddingMargin(it.obj, it.endOfInline) != 0);
     }
     if (it.obj->isText() && !static_cast<RenderText *>(it.obj)->length()) {
         return false;
     }
     if (it.obj->style()->preserveWS() || it.obj->isBR()) {
         return true;
     }
 
     switch (it.current().unicode()) {
     case 0x0009: // ASCII tab
     case 0x000A: // ASCII line feed
     case 0x000C: // ASCII form feed
     case 0x0020: // ASCII space
     case 0x200B: // Zero-width space
         return false;
     }
     return true;
 }
 
 bool RenderBlock::inlineChildNeedsLineBox(RenderObject *inlineObj) // WC: generatesLineBoxesForInlineChild
 {
     assert(inlineObj->parent() == this);
 
     BidiIterator it(this, inlineObj, 0);
     while (!it.atEnd() && !requiresLineBox(it)) {
         it.increment(nullptr, false /*skipInlines*/);
     }
 
     return !it.atEnd();
 }
 
 void RenderBlock::fitBelowFloats(int widthToFit, int &availableWidth)
 {
     assert(widthToFit > availableWidth);
 
     int floatBottom;
     int lastFloatBottom = m_height;
     int newLineWidth = availableWidth;
     while (true) {
         floatBottom = nearestFloatBottom(lastFloatBottom);
         if (!floatBottom) {
             break;
         }
 
         newLineWidth = lineWidth(floatBottom);
         lastFloatBottom = floatBottom;
         if (newLineWidth >= widthToFit) {
             break;
         }
     }
     if (newLineWidth > availableWidth) {
         m_height = lastFloatBottom;
         availableWidth = newLineWidth;
 #ifdef DEBUG_LINEBREAKS
         qCDebug(KHTML_LOG) << " new position at " << m_height << " newWidth " << availableWidth;
 #endif
     }
 }
 
 BidiIterator RenderBlock::findNextLineBreak(BidiIterator &start, BidiState &bidi)
 {
     int width = lineWidth(m_height);
     int w = 0; // the width from the start of the line up to the currently chosen breaking opportunity
     int tmpW = 0; // the accumulated width since the last chosen breaking opportunity
 #ifdef DEBUG_LINEBREAKS
     qCDebug(KHTML_LOG) << "findNextLineBreak: line at " << m_height << " line width " << width;
     qCDebug(KHTML_LOG) << "sol: " << start.obj << " " << start.pos;
 #endif
 
     BidiIterator posStart = start;
     bool hadPosStart = false;
 
     // Skip initial whitespace
     while (!start.atEnd() && !requiresLineBox(start)) {
         if (start.obj->isFloating() || start.obj->isPosWithStaticDim()) {
             RenderObject *o = start.obj;
             // add to special objects...
             if (o->isFloating()) {
                 insertFloatingObject(o);
                 positionNewFloats();
                 width = lineWidth(m_height);
             } else if (o->isPositioned()) {
                 // add midpoints to have positioned objects at the correct static location
                 // while still skipping initial whitespace.
                 if (!hadPosStart) {
                     hadPosStart = true;
                     posStart = start;
                     // include this object then stop
                     addMidpoint(BidiIterator(nullptr, o, 0));
                 } else {
                     // start/stop
                     addMidpoint(BidiIterator(nullptr, o, 0));
                     addMidpoint(BidiIterator(nullptr, o, 0));
                 }
                 setStaticPosition(this, o);
             }
         }
         start.increment(&bidi, false /*skipInlines*/);
     }
 
     if (hadPosStart && !start.atEnd()) {
         addMidpoint(start);
     }
 
     if (start.atEnd()) {
         if (hadPosStart) {
             start = posStart;
             posStart.increment();
             return posStart;
         }
         return start;
     }
 
     // This variable says we have encountered an object after which initial whitespace should be ignored (e.g. InlineFlows at the beginning of a line).
     // Either we have nothing to do, if there is no whitespace after the object... or we have to enter the ignoringSpaces state.
     // This dilemma will be resolved when we have a peek at the next object.
     bool checkShouldIgnoreInitialWhitespace = false;
 
     // This variable is used only if whitespace isn't set to PRE, and it tells us whether
     // or not we are currently ignoring whitespace.
     bool ignoringSpaces = false;
     BidiIterator ignoreStart;
 
     // This variable tracks whether the very last character we saw was a space.  We use
     // this to detect when we encounter a second space so we know we have to terminate
     // a run.
     bool currentCharacterIsSpace = false;
 
     // This variable tracks whether there is space still available on the line for floating objects.
     // Once a floating object does not fit, we wait till next linebreak before positioning more floats.
     bool floatsFitOnLine = true;
 
     RenderObject *trailingSpaceObject = nullptr;
 
     BidiIterator lBreak = start;
     InlineMinMaxIterator it(start.par, start.obj, start.endOfInline, false /*skipPositioned*/);
     InlineMinMaxIterator lastIt = it;
     int pos = start.pos;
 
     bool prevLineBrokeCleanly = previousLineBrokeAtBR;
     previousLineBrokeAtBR = false;
 
     RenderObject *o = it.current;
     while (o) {
 #ifdef DEBUG_LINEBREAKS
         qCDebug(KHTML_LOG) << "new object " << o << " width = " << w << " tmpw = " << tmpW;
 #endif
         if (o->isBR()) {
             if (w + tmpW <= width) {
                 lBreak.obj = o;
                 lBreak.pos = 0;
                 lBreak.endOfInline = it.endOfInline;
 
                 // A <br> always breaks a line, so don't let the line be collapsed
                 // away. Also, the space at the end of a line with a <br> does not
                 // get collapsed away.  It only does this if the previous line broke
                 // cleanly.  Otherwise the <br> has no effect on whether the line is
                 // empty or not.
                 if (prevLineBrokeCleanly) {
                     isLineEmpty = false;
                 }
                 trailingSpaceObject = nullptr;
                 previousLineBrokeAtBR = true;
 
                 if (!isLineEmpty) {
                     // only check the clear status for non-empty lines.
                     EClear clear = o->style()->clear();
                     if (clear != CNONE) {
                         m_clearStatus = (EClear)(m_clearStatus | clear);
                     }
                 }
             }
             goto end;
         }
         if (o->isFloatingOrPositioned()) {
             // add to special objects...
             if (o->isFloating()) {
                 insertFloatingObject(o);
                 // check if it fits in the current line.
                 // If it does, position it now, otherwise, position
                 // it after moving to next line (in newLine() func)
                 if (floatsFitOnLine && o->width() + o->marginLeft() + o->marginRight() + w + tmpW <= width) {
                     positionNewFloats();
                     width = lineWidth(m_height);
                 } else {
                     floatsFitOnLine = false;
                 }
             } else if (o->isPositioned() && o->isPosWithStaticDim()) {
                 bool needToSetStaticX;
                 bool needToSetStaticY;
                 setStaticPosition(this, o, &needToSetStaticX, &needToSetStaticY);
 
                 // If we're ignoring spaces, we have to stop and include this object and
                 // then start ignoring spaces again.
                 if (needToSetStaticX || needToSetStaticY) {
                     trailingSpaceObject = nullptr;
                     ignoreStart.obj = o;
                     ignoreStart.pos = 0;
                     if (ignoringSpaces) {
                         addMidpoint(ignoreStart); // Stop ignoring spaces.
                         addMidpoint(ignoreStart); // Start ignoring again.
                     }
                 }
             }
         } else if (o->isInlineFlow()) {
             tmpW += getBorderPaddingMargin(o, it.endOfInline);
             if (isLineEmpty) {
                 isLineEmpty = !tmpW;
             }
             if (o->isWordBreak()) { // #### shouldn't be an InlineFlow!
                 w += tmpW;
                 tmpW = 0;
                 lBreak.obj = o;
                 lBreak.pos = 0;
                 lBreak.endOfInline = it.endOfInline;
             } else if (!it.endOfInline) {
                 // this is the beginning of the line (other non-initial inline flows are handled directly when
                 // incrementing the iterator below). We want to skip initial whitespace as much as possible.
                 checkShouldIgnoreInitialWhitespace = true;
             }
         } else if (o->isReplaced() || o->isGlyph()) {
             EWhiteSpace currWS = o->style()->whiteSpace();
             EWhiteSpace lastWS = lastIt.current->style()->whiteSpace();
 
             // WinIE marquees have different whitespace characteristics by default when viewed from
             // the outside vs. the inside.  Text inside is NOWRAP, and so we altered the marquee's
             // style to reflect this, but we now have to get back to the original whitespace value
             // for the marquee when checking for line breaking.
             if (o->isHTMLMarquee() && o->layer() && o->layer()->marquee()) {
                 currWS = o->layer()->marquee()->whiteSpace();
             }
             if (lastIt.current->isHTMLMarquee() && lastIt.current->layer() && lastIt.current->layer()->marquee()) {
                 lastWS = lastIt.current->layer()->marquee()->whiteSpace();
             }
 
             // Break on replaced elements if either has normal white-space.
             if (currWS == NORMAL || lastWS == NORMAL) {
                 w += tmpW;
                 tmpW = 0;
                 lBreak.obj = o;
                 lBreak.pos = 0;
                 lBreak.endOfInline = false;
             }
 
             tmpW += o->width() + o->marginLeft() + o->marginRight();
             if (ignoringSpaces) {
                 BidiIterator startMid(nullptr, o, 0);
                 addMidpoint(startMid);
             }
             isLineEmpty = false;
             ignoringSpaces = false;
             currentCharacterIsSpace = false;
             trailingSpaceObject = nullptr;
 
             if (o->isListMarker()) {
                 checkShouldIgnoreInitialWhitespace = true;
             }
         } else if (o->isText()) {
             RenderText *t = static_cast<RenderText *>(o);
             int strlen = t->stringLength();
             int len = strlen - pos;
             QChar *str = t->text();
 
             const Font *f = t->htmlFont(m_firstLine);
             // proportional font, needs a bit more work.
             int lastSpace = pos;
             bool autoWrap = o->style()->autoWrap();
             bool preserveWS = o->style()->preserveWS();
             bool preserveLF = o->style()->preserveLF();
 #ifdef APPLE_CHANGES
             int wordSpacing = o->style()->wordSpacing();
 #endif
             bool nextIsSoftBreakable = false;
             bool checkBreakWord = autoWrap && (o->style()->wordWrap() == WWBREAKWORD);
 
             while (len) {
                 bool previousCharacterIsSpace = currentCharacterIsSpace;
                 bool isSoftBreakable = nextIsSoftBreakable;
                 nextIsSoftBreakable = false;
                 const QChar c = str[pos];
                 currentCharacterIsSpace = c.unicode() == ' ';
                 checkBreakWord &= !w; // only break words when no other breaking opportunity exists earlier
                 // on the line (even within the text object we are currently processing)
 
                 if (preserveWS || !currentCharacterIsSpace) {
                     isLineEmpty = false;
                 }
 
                 // Check for soft hyphens.  Go ahead and ignore them.
                 if (c.unicode() == SOFT_HYPHEN && pos > 0) {
                     nextIsSoftBreakable = true;
                     if (!ignoringSpaces) {
                         // Ignore soft hyphens
                         BidiIterator endMid(nullptr, o, pos - 1);
                         addMidpoint(endMid);
 
                         // Add the width up to but not including the hyphen.
                         tmpW += t->width(lastSpace, pos - lastSpace, f);
 
                         // For wrapping text only, include the hyphen.  We need to ensure it will fit
                         // on the line if it shows when we break.
                         if (o->style()->autoWrap()) {
                             const QChar softHyphen(0x00ad);
                             tmpW += f->charWidth(&softHyphen, 1, 0, true);
                         }
 
                         BidiIterator startMid(nullptr, o, pos + 1);
                         addMidpoint(startMid);
                     }
 
                     pos++;
                     len--;
                     lastSpace = pos; // Cheesy hack to prevent adding in widths of the run twice.
                     continue;
                 }
 #ifdef APPLE_CHANGES    // KDE applies wordspacing differently
                 bool applyWordSpacing = false;
 #endif
                 if (ignoringSpaces) {
                     // We need to stop ignoring spaces, if we encounter a non-space or
                     // a run that doesn't collapse spaces.
                     if (!currentCharacterIsSpace || preserveWS) {
                         // Stop ignoring spaces and begin at this
                         // new point.
                         ignoringSpaces = false;
                         lastSpace = pos; // e.g., "Foo    goo", don't add in any of the ignored spaces.
                         BidiIterator startMid(nullptr, o, pos);
                         addMidpoint(startMid);
                     } else {
                         // Just keep ignoring these spaces.
                         pos++;
                         len--;
                         continue;
                     }
                 }
                 bool isbreakablePosition = (preserveLF && c.unicode() == '\n') || (autoWrap && (isBreakable(str, pos, strlen) || isSoftBreakable));
                 if (isbreakablePosition || checkBreakWord) {
                     tmpW += t->width(lastSpace, pos - lastSpace, f);
 #ifdef APPLE_CHANGES
                     applyWordSpacing = (wordSpacing && currentCharacterIsSpace && !previousCharacterIsSpace &&
                                         !t->containsOnlyWhitespace(pos + 1, strlen - (pos + 1)));
 #endif
 #ifdef DEBUG_LINEBREAKS
                     qCDebug(KHTML_LOG) << "found space at " << pos << " in string '" << QString(str, strlen).toLatin1().constData() << "' adding " << tmpW << " new width = " << w;
 #endif
                     if (!w && autoWrap && tmpW > width) {
                         fitBelowFloats(tmpW, width);
                     }
 
                     if (autoWrap) {
                         if (w + tmpW > width) {
                             if (checkBreakWord && pos) {
                                 lBreak.obj = o;
                                 lBreak.pos = pos - 1;
                                 lBreak.endOfInline = false;
                             }
                             goto end;
                         } else if ((pos > 1 && str[pos - 1].unicode() == SOFT_HYPHEN))
                             // Subtract the width of the soft hyphen out since we fit on a line.
                         {
                             tmpW -= t->width(pos - 1, 1, f);
                         }
                     }
 
                     if (preserveLF && (str + pos)->unicode() == '\n') {
                         lBreak.obj = o;
                         lBreak.pos = pos;
                         lBreak.endOfInline = false;
 
 #ifdef DEBUG_LINEBREAKS
                         qCDebug(KHTML_LOG) << "forced break sol: " << start.obj << " " << start.pos << "   end: " << lBreak.obj << " " << lBreak.pos << "   width=" << w;
 #endif
                         return lBreak;
                     }
 
                     if (autoWrap && isbreakablePosition) {
                         w += tmpW;
                         tmpW = 0;
                         lBreak.obj = o;
                         lBreak.pos = pos;
                         lBreak.endOfInline = false;
                     }
 
                     lastSpace = pos;
 #ifdef APPLE_CHANGES
                     if (applyWordSpacing) {
                         w += wordSpacing;
                     }
 #endif
                 }
 
                 if (!ignoringSpaces && !preserveWS) {
                     // If we encounter a second space, we need to go ahead and break up this run
                     // and enter a mode where we start collapsing spaces.
                     if (currentCharacterIsSpace && previousCharacterIsSpace) {
                         ignoringSpaces = true;
 
                         // We just entered a mode where we are ignoring
                         // spaces. Create a midpoint to terminate the run
                         // before the second space.
                         addMidpoint(ignoreStart);
                         lastSpace = pos;
                     }
                 }
 
                 if (currentCharacterIsSpace && !previousCharacterIsSpace) {
                     ignoreStart.obj = o;
                     ignoreStart.pos = pos;
                 }
 
                 if (!preserveWS && currentCharacterIsSpace && !ignoringSpaces) {
                     trailingSpaceObject = o;
                 } else if (preserveWS || !currentCharacterIsSpace) {
                     trailingSpaceObject = nullptr;
                 }
 
                 pos++;
                 len--;
             }
 
             if (!ignoringSpaces) {
                 // We didn't find any space that would be beyond the line |width|.
                 // Lets add to |tmpW| the remaining width since the last space we found.
                 // Before we test this new |tmpW| however, we will have to look ahead to check
                 // if the next object/position can serve as a line breaking opportunity.
                 tmpW += t->width(lastSpace, pos - lastSpace, f);
                 if (checkBreakWord && !w && pos && tmpW > width) {
                     // Avoid doing the costly lookahead for break-word,
                     // since we know we are allowed to break.
                     lBreak.obj = o;
                     lBreak.pos = pos - 1;
                     lBreak.endOfInline = false;
                     goto end;
                 }
             }
         } else {
             KHTMLAssert(false);
         }
 
         InlineMinMaxIterator savedIt = lastIt;
         lastIt = it;
         o = it.next();
 
         // Advance the iterator to the next non-inline-flow
         while (o && o->isInlineFlow() && !o->isWordBreak()) {
             tmpW += getBorderPaddingMargin(o, it.endOfInline);
             if (isLineEmpty) {
                 isLineEmpty = !tmpW;
             }
             o = it.next();
         }
 
         // All code below, until the end of the loop, is looking ahead the |it| object we just
         // advanced to, comparing it to the previous object |lastIt|.
 
         if (checkShouldIgnoreInitialWhitespace) {
             // Check if we should switch to ignoringSpaces state
             if (!style()->preserveWS() && it.current && it.current->isText()) {
                 const RenderText *rt = static_cast<RenderText *>(it.current);
                 if (rt->stringLength() > 0 && (rt->text()[0].category() == QChar::Separator_Space || rt->text()[0] == '\n')) {
                     currentCharacterIsSpace = true;
                     ignoringSpaces = true;
                     BidiIterator endMid(nullptr, lastIt.current, 0);
                     addMidpoint(endMid);
                 }
             }
             checkShouldIgnoreInitialWhitespace = false;
         }
 
         bool autoWrap = lastIt.current->style()->autoWrap();
         bool canBreak = !lBreak.obj || !lBreak.obj->isInlineFlow() || !lBreak.obj->firstChild();
 
         bool checkForBreak = autoWrap;
         if (canBreak) {
             if (!autoWrap && w && w + tmpW > width && lBreak.obj && !lastIt.current->style()->preserveLF())
                 // ### needs explanation
             {
                 checkForBreak = true;
             } else if (it.current && lastIt.current->isText() && it.current->isText() && !it.current->isBR()) {
                 // We are looking ahead the next text object to see if it continues a word started previously,
                 // or is a line-breaking opportunity.
                 if (autoWrap || it.current->style()->autoWrap()) {
                     if (currentCharacterIsSpace)
                         // "<i>s </i>top"
                         //      _    ^
                     {
                         checkForBreak = true;
                     } else {
                         // either "<i>c</i>ontinue" or "<i>s</i> top"
                         //            _    ^               _    ^
                         checkForBreak = false;
                         RenderText *nextText = static_cast<RenderText *>(it.current);
                         if (nextText->stringLength() != 0) {
                             QChar c = nextText->text()[0];
                             // If the next item is a space, then we may try to break.
                             // Otherwise the next text run continues our word (and so it needs to
                             // keep adding to |tmpW|).
                             if (c == ' ' || c == '\t' || (c == '\n' && !it.current->style()->preserveLF())) {
                                 checkForBreak = true;
                             }
                         }
 
                         bool willFitOnLine = (w + tmpW <= width);
                         if (!willFitOnLine && !w) {
                             fitBelowFloats(tmpW, width);
                             willFitOnLine = tmpW <= width;
                         }
                         bool canPlaceOnLine = willFitOnLine || !autoWrap;
                         if (canPlaceOnLine && checkForBreak) {
                             w += tmpW;
                             tmpW = 0;
                             lBreak.obj = it.current;
                             lBreak.pos = 0;
                             lBreak.endOfInline = it.endOfInline;
                         }
                     }
                 }
             }
 
             if (checkForBreak && (w + tmpW > width)) {
                 // if we have floats, try to get below them.
                 if (currentCharacterIsSpace && !ignoringSpaces && !lastIt.current->style()->preserveWS()) {
                     trailingSpaceObject = nullptr;
                 }
 
                 if (w) {
                     goto end;
                 }
                 fitBelowFloats(tmpW, width);
 
                 // |width| may have been adjusted because we got shoved down past a float (thus
                 // giving us more room), so we need to retest, and only jump to
                 // the end label if we still don't fit on the line. -dwh
                 if (w + tmpW > width) {
                     it = lastIt;
                     lastIt = savedIt;
                     o = it.current;
                     goto end;
                 }
             }
         }
         if (!lastIt.current->isFloatingOrPositioned() && lastIt.current->isReplaced() && lastIt.current->style()->autoWrap()) {
             // Go ahead and add in tmpW.
             w += tmpW;
             tmpW = 0;
             lBreak.obj = o;
             lBreak.pos = 0;
             lBreak.endOfInline = it.endOfInline;
         }
 
         // Clear out our character space bool, since inline <pre>s don't collapse whitespace
         // with adjacent inline normal/nowrap spans.
         if (lastIt.current->style()->preserveWS()) {
             currentCharacterIsSpace = false;
         }
 
         pos = 0;
     }
 
 #ifdef DEBUG_LINEBREAKS
     qCDebug(KHTML_LOG) << "end of par, width = " << width << " linewidth = " << w + tmpW;
 #endif
     if (w + tmpW <= width || (lastIt.current && !lastIt.current->style()->autoWrap())) {
         lBreak.obj = nullptr;
         lBreak.pos = 0;
         lBreak.endOfInline = false;
     }
 
 end:
     if (lBreak == start && !lBreak.obj->isBR()) {
         // Having an |lBreak| identical to our |start| at this point means the first suitable
         // break point |it.current| that we found was past |width|, so we jumped to the |end| label
         // before we could set this (overflowing) breaking opportunity. Let's set it now.
         if (style()->whiteSpace() == PRE) {
             // FIXME: Don't really understand this case.
             if (pos != 0) {
                 lBreak.obj = o;
                 lBreak.pos = pos - 1;
                 lBreak.endOfInline = it.endOfInline;
             } else {
                 lBreak.obj = lastIt.current;
                 lBreak.pos = lastIt.current->isText() ? lastIt.current->length() : 0;
                 lBreak.endOfInline = lastIt.endOfInline;
             }
         } else if (lBreak.obj) {
             lBreak.obj = o;
             lBreak.pos = (o && o->isText() ? pos : 0);
             lBreak.endOfInline = it.endOfInline;
         }
     }
 
     if (hadPosStart) {
         start = posStart;
     }
 
     if (lBreak == start) {
         // make sure we consume at least one char/object.
         lBreak.increment();
     }
 
 #ifdef DEBUG_LINEBREAKS
     qCDebug(KHTML_LOG) << "regular break sol: " << start.obj << " " << start.pos << "   end: " << lBreak.obj << " " << lBreak.pos << "   width=" << w;
 #endif
 
     // Sanity check our midpoints.
     checkMidpoints(lBreak);
 
     if (trailingSpaceObject) {
         // This object is either going to be part of the last midpoint, or it is going
         // to be the actual endpoint.  In both cases we just decrease our pos by 1 level to
         // exclude the space, allowing it to - in effect - collapse into the newline.
         if (sNumMidpoints % 2 == 1) {
             BidiIterator *midpoints = smidpoints->data();
             midpoints[sNumMidpoints - 1].pos--;
         }
         //else if (lBreak.pos > 0)
         //    lBreak.pos--;
         else if (lBreak.obj == nullptr && trailingSpaceObject->isText()) {
             // Add a new end midpoint that stops right at the very end.
             RenderText *text = static_cast<RenderText *>(trailingSpaceObject);
             unsigned pos = text->length() >= 2 ? text->length() - 2 : UINT_MAX;
             BidiIterator endMid(nullptr, trailingSpaceObject, pos);
             addMidpoint(endMid);
         }
     }
 
     // We might have made lBreak an iterator that points past the end
     // of the object. Do this adjustment to make it point to the start
     // of the next object instead to avoid confusing the rest of the
     // code.
     if (lBreak.pos > 0) {
         lBreak.pos--;
         lBreak.increment();
     }
 
     if (lBreak.obj && lBreak.pos >= 2 && lBreak.obj->isText()) {
         // For soft hyphens on line breaks, we have to chop out the midpoints that made us
         // ignore the hyphen so that it will render at the end of the line.
         QChar c = static_cast<RenderText *>(lBreak.obj)->text()[lBreak.pos - 1];
         if (c.unicode() == SOFT_HYPHEN) {
             chopMidpointsAt(lBreak.obj, lBreak.pos - 2);
         }
     }
 
     return lBreak;
 }
 
 void RenderBlock::checkLinesForOverflow()
 {
     for (RootInlineBox *curr = static_cast<khtml::RootInlineBox *>(firstLineBox()); curr; curr = static_cast<khtml::RootInlineBox *>(curr->nextLineBox())) {
 //         m_overflowLeft = min(curr->leftOverflow(), m_overflowLeft);
         m_overflowTop = qMin(curr->topOverflow(), m_overflowTop);
 //         m_overflowWidth = max(curr->rightOverflow(), m_overflowWidth);
         m_overflowHeight = qMax(curr->bottomOverflow(), m_overflowHeight);
     }
 }
 
 void RenderBlock::deleteEllipsisLineBoxes()
 {
     for (RootInlineBox *curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
         curr->clearTruncation();
     }
 }
 
 void RenderBlock::checkLinesForTextOverflow()
 {
     // Determine the width of the ellipsis using the current font.
     QChar ellipsis = 0x2026; // FIXME: CSS3 says this is configurable, also need to use 0x002E (FULL STOP) if 0x2026 not renderable
     static QString ellipsisStr(ellipsis);
     const Font &firstLineFont = style(true)->htmlFont();
     const Font &font = style()->htmlFont();
     int firstLineEllipsisWidth = firstLineFont.charWidth(&ellipsis, 1, 0, true /*fast algo*/);
     int ellipsisWidth = (font == firstLineFont) ? firstLineEllipsisWidth : font.charWidth(&ellipsis, 1, 0, true /*fast algo*/);
 
     // For LTR text truncation, we want to get the right edge of our padding box, and then we want to see
     // if the right edge of a line box exceeds that.  For RTL, we use the left edge of the padding box and
     // check the left edge of the line box to see if it is less
     // Include the scrollbar for overflow blocks, which means we want to use "contentWidth()"
     bool ltr = style()->direction() == LTR;
     for (RootInlineBox *curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
         int blockEdge = ltr ? rightOffset(curr->yPos()) : leftOffset(curr->yPos());
         int lineBoxEdge = ltr ? curr->xPos() + curr->width() : curr->xPos();
         if ((ltr && lineBoxEdge > blockEdge) || (!ltr && lineBoxEdge < blockEdge)) {
             // This line spills out of our box in the appropriate direction.  Now we need to see if the line
             // can be truncated.  In order for truncation to be possible, the line must have sufficient space to
             // accommodate our truncation string, and no replaced elements (images, tables) can overlap the ellipsis
             // space.
             int width = curr == firstRootBox() ? firstLineEllipsisWidth : ellipsisWidth;
             if (curr->canAccommodateEllipsis(ltr, blockEdge, lineBoxEdge, width)) {
                 curr->placeEllipsis(ellipsisStr, ltr, blockEdge, width);
             }
         }
     }
 }
 
 // For --enable-final
 #undef BIDI_DEBUG
 #undef DEBUG_LINEBREAKS
 #undef DEBUG_LAYOUT
 
 }