File indexing completed on 2024-04-28 13:37:59

 // clang-format off
 /*
  *  This file is part of KDiff3.
  *
  * SPDX-FileCopyrightText: 2002-2011 Joachim Eibl, joachim.eibl at gmx.de
  * SPDX-FileCopyrightText: 2018-2020 Michael Reeves reeves.87@gmail.com
  * SPDX-License-Identifier: GPL-2.0-or-later
 */
 // clang-format on
 
 #include "diff.h"
 #include <QtGlobal>
 
 #include "gnudiff_diff.h"
 #include "Logging.h"
 #include "options.h"
 #include "ProgressProxy.h"
 #include "Utils.h"
 
 #include <algorithm>           // for min
 #include <cstdlib>
 #include <ctype.h>
 #include <exception>
 #include <memory>
 #include <optional>
 #include <utility>             // for swap
 
 #ifndef AUTOTEST
 #include <KLocalizedString>
 #include <KMessageBox>
 #endif
 
 #include <QRegularExpression>
 #include <QSharedPointer>
 #include <QTextStream>
 
 extern std::unique_ptr<Options> gOptions;
 
 constexpr bool g_bIgnoreWhiteSpace = true;
 
 QSharedPointer<DiffBufferInfo> Diff3Line::m_pDiffBufferInfo = QSharedPointer<DiffBufferInfo>::create();
 
 qint32 LineData::width(qint32 tabSize) const
 {
     const QString pLine = getLine();
     qint32 w = 0;
     qint32 j = 0;
     for(QtSizeType i = 0; i < size(); ++i)
     {
         if(pLine[i] == '\t')
         {
             for(j %= tabSize; j < tabSize; ++j)
                 ++w;
             j = 0;
         }
         else
         {
             ++w;
             ++j;
         }
     }
     return w;
 }
 
 class StringIter {
     QString::const_iterator ptr;
     QString::const_iterator end;
 
 public:
     StringIter(QString const& s)
         : ptr(s.begin())
         , end(s.end())
     {}
 
     bool hasPeek() const {
         return ptr < end;
     }
 
     std::optional<QChar> tryPeek() const {
         if (ptr < end) {
             return *ptr;
         } else {
             return {};
         }
     }
 
     void next() {
         assert(ptr < end);
         ptr++;
     }
 };
 
 /*
     Implement support for g_bIgnoreWhiteSpace
 */
 bool LineData::equal(const LineData& l1, const LineData& l2)
 {
     if(l1.getLine() == nullptr || l2.getLine() == nullptr) return false;
 
     if(g_bIgnoreWhiteSpace)
     {
         // Ignore white space diff
         const QString line1 = l1.getLine(), line2 = l2.getLine();
         StringIter p1{line1};
         StringIter p2{line2};
 
         for(; ; p1.next(), p2.next())
         {
             // Advance to the next non-whitespace character or EOL.
             while (p1.hasPeek() && isspace(p1.tryPeek()->toLatin1())) {
                 p1.next();
             }
             while (p2.hasPeek() && isspace(p2.tryPeek()->toLatin1())) {
                 p2.next();
             }
 
             // If the two strings differ outside of whitespace, or either ends earlier, return false.
             if(p1.tryPeek() != p2.tryPeek())
                 return false;
 
             // If both strings end together, return true.
             if (!p1.hasPeek() && !p2.hasPeek()) {
                 return true;
             }
 
             // Test remaining characters.
         }
     }
     else
     {
         const QString line1 = l1.getLine(), line2 = l2.getLine();
         return (l1.size() == l2.size() && QString::compare(line1, line2) == 0);
     }
 }
 
 // First step
 void Diff3LineList::calcDiff3LineListUsingAB(const DiffList* pDiffListAB)
 {
     // First make d3ll for AB (from pDiffListAB)
 
     LineRef lineA = 0;
     LineRef lineB = 0;
 
     qCInfo(kdiffMain) << "Enter: calcDiff3LineListUsingAB";
     for(Diff d: *pDiffListAB)
     {
         while(d.numberOfEquals() > 0)
         {
             Diff3Line d3l;
 
             d3l.bAEqB = true;
             d3l.setLineA(lineA);
             d3l.setLineB(lineB);
             d.adjustNumberOfEquals(-1);
             ++lineA;
             ++lineB;
 
             qCDebug(kdiffCore) << "lineA = " << d3l.getLineA() << ", lineB = " << d3l.getLineB() ;
             push_back(d3l);
         }
 
         while(d.diff1() > 0 && d.diff2() > 0)
         {
             Diff3Line d3l;
 
             d3l.setLineA(lineA);
             d3l.setLineB(lineB);
             d.adjustDiff1(-1);
             d.adjustDiff2(-1);
             ++lineA;
             ++lineB;
 
             qCDebug(kdiffCore) << "lineA = " << d3l.getLineA() << ", lineB = " << d3l.getLineB() ;
             push_back(d3l);
         }
 
         while(d.diff1() > 0)
         {
             Diff3Line d3l;
 
             d3l.setLineA(lineA);
             d.adjustDiff1(-1);
             ++lineA;
 
             qCDebug(kdiffCore) << "lineA = " << d3l.getLineA() << ", lineB = " << d3l.getLineB() ;
             push_back(d3l);
         }
 
         while(d.diff2() > 0)
         {
             Diff3Line d3l;
 
             d3l.setLineB(lineB);
             d.adjustDiff2(-1);
             ++lineB;
 
             qCDebug(kdiffCore) << "lineA = " << d3l.getLineA() << ", lineB = " << d3l.getLineB() ;
             push_back(d3l);
         }
     }
     qCInfo(kdiffMain) << "Leave: calcDiff3LineListUsingAB" ;
 }
 
 // Second step
 void Diff3LineList::calcDiff3LineListUsingAC(const DiffList* pDiffListAC)
 {
     ////////////////
     // Now insert data from C using pDiffListAC
 
     Diff3LineList::iterator i3 = begin();
     LineRef lineA = 0;
     LineRef lineC = 0;
 
     for(Diff d: *pDiffListAC)
     {
         assert(d.diff1() <= limits<LineType>::max() && d.diff2() <= limits<LineType>::max());
 
         while(d.numberOfEquals() > 0)
         {
             Diff3Line d3l;
 
             // Find the corresponding lineA
             while(i3->getLineA() != lineA && i3 != end())
                 ++i3;
             assert(i3 != end());
 
             i3->setLineC(lineC);
             i3->bAEqC = true;
             i3->bBEqC = i3->isEqualAB();
 
             d.adjustNumberOfEquals(-1);
             ++lineA;
             ++lineC;
             ++i3;
         }
         assert(i3 != end() || (d.diff1() == 0 && d.diff2() == 0));
 
         while(d.diff1() > 0 && d.diff2() > 0)
         {
             Diff3Line d3l;
 
             d3l.setLineC(lineC);
             insert(i3, d3l);
             d.adjustDiff1(-1);
             d.adjustDiff2(-1);
             ++lineA;
             ++lineC;
         }
 
         lineA += (LineRef)d.diff1();
 
         while(d.diff2() > 0)
         {
             Diff3Line d3l;
 
             d3l.setLineC(lineC);
             insert(i3, d3l);
             d.adjustDiff2(-1);
             ++lineC;
         }
     }
 }
 
 // Third step
 void Diff3LineList::calcDiff3LineListUsingBC(const DiffList* pDiffListBC)
 {
     ////////////////
     // Now improve the position of data from C using pDiffListBC
     // If a line from C equals a line from A then it is in the
     // same Diff3Line already.
     // If a line from C equals a line from B but not A, this
     // information will be used here.
 
     Diff3LineList::iterator i3b = begin();
     Diff3LineList::iterator i3c = begin();
     LineRef lineB = 0;
     LineRef lineC = 0;
 
     for(Diff d: *pDiffListBC)
     {
         while(d.numberOfEquals() > 0)
         {
             Diff3Line d3l;
             // Find the corresponding lineB and lineC
             while(i3b != end() && i3b->getLineB() != lineB)
                 ++i3b;
 
             while(i3c != end() && i3c->getLineC() != lineC)
                 ++i3c;
 
             assert(i3b != end());
             assert(i3c != end());
 
             if(i3b == i3c)
             {
                 assert(i3b->getLineC() == lineC);
                 i3b->bBEqC = true;
             }
             else
             {
                 // Is it possible to move this line up?
                 // Test if no other B's are used between i3c and i3b
 
                 // First test which is before: i3c or i3b ?
                 Diff3LineList::iterator i3c1 = i3c;
                 Diff3LineList::iterator i3b1 = i3b;
                 while(i3c1 != i3b && i3b1 != i3c)
                 {
                     assert(i3b1 != end() || i3c1 != end());
                     if(i3c1 != end()) ++i3c1;
                     if(i3b1 != end()) ++i3b1;
                 }
 
                 if(i3c1 == i3b && !i3b->isEqualAB()) // i3c before i3b
                 {
                     Diff3LineList::iterator i3 = i3c;
                     quint32 nofDisturbingLines = 0;
                     while(i3 != i3b && i3 != end())
                     {
                         if(i3->getLineB().isValid())
                             ++nofDisturbingLines;
                         ++i3;
                     }
 
                     if(nofDisturbingLines > 0)
                     {
                         Diff3LineList::iterator i3_last_equal_A = end();
 
                         i3 = i3c;
                         while(i3 != i3b)
                         {
                             if(i3->isEqualAB())
                             {
                                 i3_last_equal_A = i3;
                             }
                             ++i3;
                         }
 
                         /* If i3_last_equal_A isn't still set to d3ll.end(), then
                         * we've found a line in A that is equal to one in B
                         * somewhere between i3c and i3b
                         */
                         bool before_or_on_equal_line_in_A = (i3_last_equal_A != end());
 
                         // Move the disturbing lines up, out of sight.
                         i3 = i3c;
                         while(i3 != i3b)
                         {
                             if(i3->getLineB().isValid() ||
                             (before_or_on_equal_line_in_A && i3->getLineA().isValid()))
                             {
                                 d3l.setLineB(i3->getLineB());
                                 i3->setLineB(LineRef::invalid);
 
                                 // Move A along if it matched B
                                 if(before_or_on_equal_line_in_A)
                                 {
                                     d3l.setLineA(i3->getLineA());
                                     d3l.bAEqB = i3->isEqualAB();
                                     i3->setLineA(LineRef::invalid);
                                     i3->bAEqC = false;
                                 }
 
                                 i3->bAEqB = false;
                                 i3->bBEqC = false;
                                 insert(i3c, d3l);
                             }
 
                             if(i3 == i3_last_equal_A)
                             {
                                 before_or_on_equal_line_in_A = false;
                             }
 
                             ++i3;
                         }
                         //Not currently needed as we get here everytime nofDisturbingLines > 0
                         //nofDisturbingLines = 0;
                     }
 
                     // Was checking if nofDisturbingLines == 0 which would always be true. See above.
                     // Yes, the line from B can be moved.
                     i3b->setLineB(LineRef::invalid); // This might leave an empty line: removed later.
                     i3b->bAEqB = false;
                     i3b->bBEqC = false;
                     i3c->setLineB(lineB);
                     i3c->bBEqC = true;
                     i3c->bAEqB = i3c->isEqualAC();
                 }
                 else if(i3b1 == i3c && !i3c->isEqualAC())
                 {
                     Diff3LineList::iterator i3 = i3b;
                     quint32 nofDisturbingLines = 0;
                     while(i3 != i3c && i3 != end())
                     {
                         if(i3->getLineC().isValid())
                             ++nofDisturbingLines;
                         ++i3;
                     }
 
                     if(nofDisturbingLines > 0)
                     {
                         Diff3LineList::iterator i3_last_equal_A = end();
 
                         i3 = i3b;
                         while(i3 != i3c)
                         {
                             if(i3->isEqualAC())
                             {
                                 i3_last_equal_A = i3;
                             }
                             ++i3;
                         }
 
                         /* If i3_last_equal_A isn't still set to d3ll.end(), then
                         * we've found a line in A that is equal to one in C
                         * somewhere between i3b and i3c
                         */
                         bool before_or_on_equal_line_in_A = (i3_last_equal_A != end());
 
                         // Move the disturbing lines up.
                         i3 = i3b;
                         while(i3 != i3c)
                         {
                             if(i3->getLineC().isValid() ||
                             (before_or_on_equal_line_in_A && i3->getLineA().isValid()))
                             {
                                 d3l.setLineC(i3->getLineC());
                                 i3->setLineC(LineRef::invalid);
 
                                 // Move A along if it matched C
                                 if(before_or_on_equal_line_in_A)
                                 {
                                     d3l.setLineA(i3->getLineA());
                                     d3l.bAEqC = i3->isEqualAC();
                                     i3->setLineA(LineRef::invalid);
                                     i3->bAEqB = false;
                                 }
 
                                 i3->bAEqC = false;
                                 i3->bBEqC = false;
                                 insert(i3b, d3l);
                             }
 
                             if(i3 == i3_last_equal_A)
                             {
                                 before_or_on_equal_line_in_A = false;
                             }
 
                             ++i3;
                         }
                         //Not currently needed as we get here everytime nofDisturbingLines > 0
                         //nofDisturbingLines = 0;
                     }
 
                     // Only do this if nofDisturbingLines == 0 currently always true
                     // Yes, the line from C can be moved.
                     i3c->setLineC(LineRef::invalid); // This might leave an empty line: removed later.
                     i3c->bAEqC = false;
                     i3c->bBEqC = false;
                     i3b->setLineC(lineC);
                     i3b->bBEqC = true;
                     i3b->bAEqC = i3b->isEqualAB();
                 }
             }
 
             d.adjustNumberOfEquals(-1);
             ++lineB;
             ++lineC;
             ++i3b;
             ++i3c;
         }
 
         while(d.diff1() > 0)
         {
             Diff3Line d3l;
             Diff3LineList::iterator i3 = i3b;
 
             while(i3->getLineB() != lineB)
                 ++i3;
             if(i3 != i3b && !i3->isEqualAB())
             {
                 // Take B from this line and move it up as far as possible
                 d3l.setLineB(lineB);
                 insert(i3b, d3l);
                 i3->setLineB(LineRef::invalid);
             }
             else
             {
                 i3b = i3;
             }
             d.adjustDiff1(-1);
             ++lineB;
             ++i3b;
 
             if(d.diff2() > 0)
             {
                 d.adjustDiff2(-1);
                 ++lineC;
             }
         }
 
         lineC += (LineRef)d.diff2();
     }
     /*
    Diff3LineList::iterator it = d3ll.begin();
    qint32 li=0;
    for( ; it!=d3ll.end(); ++it, ++li )
    {
       printf( "%4d %4d %4d %4d  A%c=B A%c=C B%c=C\n",
          li, it->getLineA(), it->getLineB(), it->getLineC(),
          it->isEqualAB() ? '=' : '!', it->isEqualAC() ? '=' : '!', it->isEqualBC() ? '=' : '!' );
    }
    printf("\n");*/
 }
 
 // Test if the move would pass a barrier. Return true if not.
 bool ManualDiffHelpList::isValidMove(LineRef line1, LineRef line2, e_SrcSelector winIdx1, e_SrcSelector winIdx2) const
 {
     if(line1.isValid() && line2.isValid())
     {
         for(const ManualDiffHelpEntry& mdhe: *this)
         {
             if(!mdhe.isValidMove(line1, line2, winIdx1, winIdx2)) return false;
         }
     }
     return true; // no barrier passed.
 }
 
 void ManualDiffHelpList::insertEntry(e_SrcSelector winIdx, LineRef firstLine, LineRef lastLine)
 {
     // The manual diff help list must be sorted and compact.
     // "Compact" means that upper items can't be empty if lower items contain data.
 
     // First insert the new item without regarding compactness.
     // If the new item overlaps with previous items then the previous items will be removed.
 
     ManualDiffHelpEntry mdhe(winIdx, firstLine, lastLine);
 
     ManualDiffHelpList::iterator i;
     for(i = begin(); i != end(); ++i)
     {
         LineRef& l1 = i->firstLine(winIdx);
         LineRef& l2 = i->lastLine(winIdx);
         if(l1.isValid() && l2.isValid())
         {
             if((firstLine <= l1 && lastLine >= l1) || (firstLine <= l2 && lastLine >= l2))
             {
                 // overlap
                 l1.invalidate();
                 l2.invalidate();
             }
             else if(firstLine < l1 && lastLine < l1)
             {
                 // insert before this position
                 insert(i, mdhe);
                 break;
             }
         }
     }
     if(i == end())
     {
         insert(i, mdhe);
     }
 
     // Now make the list compact
     for(i = begin(); i != end();)
     {
         ManualDiffHelpList::iterator next = std::next(i);
         if(next != end())
         {
             for(e_SrcSelector wIdx = e_SrcSelector::A; wIdx != e_SrcSelector::Invalid; wIdx = nextSelector(wIdx))
             {
                 if(!i->firstLine(wIdx).isValid() && next->firstLine(wIdx).isValid())
                 {
                     std::swap(i->firstLine(wIdx), next->firstLine(wIdx));
                     std::swap(i->lastLine(wIdx), next->lastLine(wIdx));
                 }
             }
         }
         //Delete completely empty entries
         if(*i == ManualDiffHelpEntry())
             erase(i);
         i = next;
     }
 }
 
 bool ManualDiffHelpEntry::isValidMove(LineRef line1, LineRef line2, e_SrcSelector winIdx1, e_SrcSelector winIdx2) const
 {
     // Barrier
     LineRef l1 = winIdx1 == e_SrcSelector::A ? lineA1 : winIdx1 == e_SrcSelector::B ? lineB1 : lineC1;
     LineRef l2 = winIdx2 == e_SrcSelector::A ? lineA1 : winIdx2 == e_SrcSelector::B ? lineB1 : lineC1;
 
     if(l1.isValid() && l2.isValid())
     {
         if((line1 >= l1 && line2 < l2) || (line1 < l1 && line2 >= l2))
             return false;
         l1 = winIdx1 == e_SrcSelector::A ? lineA2 : winIdx1 == e_SrcSelector::B ? lineB2 : lineC2;
         l2 = winIdx2 == e_SrcSelector::A ? lineA2 : winIdx2 == e_SrcSelector::B ? lineB2 : lineC2;
         ++l1;
         ++l2;
         if((line1 >= l1 && line2 < l2) || (line1 < l1 && line2 >= l2))
             return false;
     }
 
     return true;
 }
 
 qint32 ManualDiffHelpEntry::calcManualDiffFirstDiff3LineIdx(const Diff3LineVector& d3lv)
 {
     QtSizeType i;
     for(i = 0; i < d3lv.size(); ++i)
     {
         const Diff3Line* d3l = d3lv[i];
         if((lineA1.isValid() && lineA1 == d3l->getLineA()) ||
            (lineB1.isValid() && lineB1 == d3l->getLineB()) ||
            (lineC1.isValid() && lineC1 == d3l->getLineC()))
             return SafeInt<qint32>(i);
     }
     return -1;
 }
 
 void DiffList::runDiff(const std::shared_ptr<LineDataVector>& p1, const size_t index1, LineRef size1, const std::shared_ptr<LineDataVector>& p2, const size_t index2, LineRef size2)
 {
     ProgressScope pp;
     static GnuDiff gnuDiff; // All values are initialized with zeros.
 
     ProgressProxy::setCurrent(0);
 
     clear();
     if(p1->empty() || (*p1)[index1].getBuffer() == nullptr || p2->empty() || (*p2)[index2].getBuffer() == nullptr || size1 == 0 || size2 == 0)
     {
         if(!p1->empty() && !p2->empty() && (*p1)[index1].getBuffer() == nullptr && (*p2)[index2].getBuffer() == nullptr && size1 == size2)
             push_back(Diff(size1, 0, 0));
         else
         {
             push_back(Diff(0, size1, size2));
         }
     }
     else
     {
         assert((size_t)size1 < p1->size() && (size_t)size2 < p2->size());
 
         GnuDiff::comparison comparisonInput;
         memset(&comparisonInput, 0, sizeof(comparisonInput));
         comparisonInput.parent = nullptr;
         comparisonInput.file[0].buffer = (*p1)[index1].getBuffer()->unicode() + (*p1)[index1].getOffset();                                         //ptr to buffer
         comparisonInput.file[0].buffered = ((*p1)[index1 + size1 - 1].getOffset() + (*p1)[index1 + size1 - 1].size() - (*p1)[index1].getOffset()); // size of buffer
         comparisonInput.file[1].buffer = (*p2)[index2].getBuffer()->unicode() + (*p2)[index2].getOffset();                                         //ptr to buffer
         comparisonInput.file[1].buffered = ((*p2)[index2 + size2 - 1].getOffset() + (*p2)[index2 + size2 - 1].size() - (*p2)[index2].getOffset()); // size of buffer
 
         gnuDiff.ignore_white_space = GnuDiff::IGNORE_ALL_SPACE; // I think nobody needs anything else ...
         gnuDiff.bIgnoreWhiteSpace = true;
         gnuDiff.bIgnoreNumbers = gOptions->m_bIgnoreNumbers;
         gnuDiff.minimal = gOptions->m_bTryHard;
         gnuDiff.ignore_case = false;
         GnuDiff::change* script = gnuDiff.diff_2_files(&comparisonInput);
 
         LineRef equalLinesAtStart = (LineRef)comparisonInput.file[0].prefix_lines;
         LineRef currentLine1 = 0;
         LineRef currentLine2 = 0;
         GnuDiff::change* p = nullptr;
         for(GnuDiff::change* e = script; e; e = p)
         {
             Diff d((LineType)(e->line0 - currentLine1), e->deleted, e->inserted);
             assert(d.numberOfEquals() == e->line1 - currentLine2);
 
             currentLine1 += LineRef((quint64)d.numberOfEquals() + d.diff1());
             currentLine2 += LineRef((quint64)d.numberOfEquals() + d.diff2());
             assert(currentLine1 <= size1 && currentLine2 <= size2);
             push_back(d);
 
             p = e->link;
             free(e);
         }
 
         if(empty())
         {
             qint32 numofEquals = std::min(size1, size2);
             Diff d(numofEquals, size1 - numofEquals, size2 - numofEquals);
 
             push_back(d);
         }
         else
         {
             front().adjustNumberOfEquals(equalLinesAtStart);
             currentLine1 += equalLinesAtStart;
             currentLine2 += equalLinesAtStart;
 
             LineType nofEquals = std::min(size1 - currentLine1, size2 - currentLine2);
             if(nofEquals == 0)
             {
                 back().adjustDiff1(size1 - currentLine1);
                 back().adjustDiff2(size2 - currentLine2);
             }
             else
             {
                 Diff d(nofEquals, size1 - currentLine1 - nofEquals, size2 - currentLine2 - nofEquals);
                 push_back(d);
             }
         }
     }
 #ifndef NDEBUG
     verify(size1, size2);
 #endif
     ProgressProxy::setCurrent(1);
 }
 
 #ifndef NDEBUG
 // Verify difflist
 void DiffList::verify(const LineRef size1, const LineRef size2)
 {
     LineRef l1 = 0;
     LineRef l2 = 0;
 
     for(const Diff& curDiff: *this)
     {
         assert(curDiff.numberOfEquals() >= 0);
         assert(curDiff.diff1() <= limits<LineType>::max() && curDiff.diff2() <= limits<LineType>::max());
         l1 += curDiff.numberOfEquals() + LineRef(curDiff.diff1());
         l2 += curDiff.numberOfEquals() + LineRef(curDiff.diff2());
     }
 
     assert(l1 == size1 && l2 == size2);
 }
 #endif
 
 void ManualDiffHelpList::runDiff(const std::shared_ptr<LineDataVector>& p1, LineRef size1, const std::shared_ptr<LineDataVector>& p2, LineRef size2, DiffList& diffList,
                                  e_SrcSelector winIdx1, e_SrcSelector winIdx2)
 {
     diffList.clear();
     DiffList diffList2;
 
     qint32 l1begin = 0;
     qint32 l2begin = 0;
 
     for(const ManualDiffHelpEntry& mdhe: *this)
     {
         LineRef l1end = mdhe.getLine1(winIdx1);
         LineRef l2end = mdhe.getLine1(winIdx2);
 
         if(l1end.isValid() && l2end.isValid())
         {
             diffList2.runDiff(p1, l1begin, l1end - l1begin, p2, l2begin, l2end - l2begin);
             diffList.splice(diffList.end(), diffList2);
             l1begin = l1end;
             l2begin = l2end;
 
             l1end = mdhe.getLine2(winIdx1);
             l2end = mdhe.getLine2(winIdx2);
 
             if(l1end.isValid() && l2end.isValid())
             {
                 ++l1end; // point to line after last selected line
                 ++l2end;
                 diffList2.runDiff(p1, l1begin, l1end - l1begin, p2, l2begin, l2end - l2begin);
                 diffList.splice(diffList.end(), diffList2);
                 l1begin = l1end;
                 l2begin = l2end;
             }
         }
     }
     diffList2.runDiff(p1, l1begin, size1 - l1begin, p2, l2begin, size2 - l2begin);
     diffList.splice(diffList.end(), diffList2);
 }
 
 void Diff3LineList::correctManualDiffAlignment(ManualDiffHelpList* pManualDiffHelpList)
 {
     if(pManualDiffHelpList->empty())
         return;
 
     // If a line appears unaligned in comparison to the manual alignment, correct this.
 
     ManualDiffHelpList::iterator iMDHL;
     for(iMDHL = pManualDiffHelpList->begin(); iMDHL != pManualDiffHelpList->end(); ++iMDHL)
     {
         Diff3LineList::iterator i3 = begin();
         e_SrcSelector missingWinIdx = e_SrcSelector::None;
         qint32 alignedSum = (!iMDHL->getLine1(e_SrcSelector::A).isValid() ? 0 : 1) + (!iMDHL->getLine1(e_SrcSelector::B).isValid() ? 0 : 1) + (!iMDHL->getLine1(e_SrcSelector::C).isValid() ? 0 : 1);
         if(alignedSum == 2)
         {
             // If only A & B are aligned then let C rather be aligned with A
             // If only A & C are aligned then let B rather be aligned with A
             // If only B & C are aligned then let A rather be aligned with B
             missingWinIdx = !iMDHL->getLine1(e_SrcSelector::A).isValid() ? e_SrcSelector::A : (!iMDHL->getLine1(e_SrcSelector::B).isValid() ? e_SrcSelector::B : e_SrcSelector::C);
         }
         else if(alignedSum <= 1)
         {
             return;
         }
 
         // At the first aligned line, move up the two other lines into new d3ls until the second input is aligned
         // Then move up the third input until all three lines are aligned.
         e_SrcSelector wi = e_SrcSelector::None;
         for(; i3 != end(); ++i3)
         {
             for(wi = e_SrcSelector::A; wi != e_SrcSelector::Invalid; wi=nextSelector(wi))
             {
                 if(i3->getLineInFile(wi).isValid() && iMDHL->firstLine(wi) == i3->getLineInFile(wi))
                     break;
             }
             if(wi != e_SrcSelector::Invalid)
                 break;
         }
 
         if(wi >= e_SrcSelector::A && wi <= e_SrcSelector::Max)
         {
             // Found manual alignment for one source
             Diff3LineList::iterator iDest = i3;
 
             // Move lines up until the next firstLine is found. Omit wi from move and search.
             e_SrcSelector wi2 = e_SrcSelector::None;
             for(; i3 != end(); ++i3)
             {
                 for(wi2 = e_SrcSelector::A; wi2 != e_SrcSelector::Invalid; wi2 = nextSelector(wi2))
                 {
                     if(wi != wi2 && i3->getLineInFile(wi2).isValid() && iMDHL->firstLine(wi2) == i3->getLineInFile(wi2))
                         break;
                 }
                 if(wi2 == e_SrcSelector::Invalid)
                 { // Not yet found
                     // Move both others up
                     Diff3Line d3l;
                     // Move both up
                     if(wi == e_SrcSelector::A) // Move B and C up
                     {
                         d3l.bBEqC = i3->isEqualBC();
                         d3l.setLineB(i3->getLineB());
                         d3l.setLineC(i3->getLineC());
                         i3->setLineB(LineRef::invalid);
                         i3->setLineC(LineRef::invalid);
                     }
                     if(wi == e_SrcSelector::B) // Move A and C up
                     {
                         d3l.bAEqC = i3->isEqualAC();
                         d3l.setLineA(i3->getLineA());
                         d3l.setLineC(i3->getLineC());
                         i3->setLineA(LineRef::invalid);
                         i3->setLineC(LineRef::invalid);
                     }
                     if(wi == e_SrcSelector::C) // Move A and B up
                     {
                         d3l.bAEqB = i3->isEqualAB();
                         d3l.setLineA(i3->getLineA());
                         d3l.setLineB(i3->getLineB());
                         i3->setLineA(LineRef::invalid);
                         i3->setLineB(LineRef::invalid);
                     }
                     i3->bAEqB = false;
                     i3->bAEqC = false;
                     i3->bBEqC = false;
                     insert(iDest, d3l);
                 }
                 else
                 {
                     // align the found line with the line we already have here
                     if(i3 != iDest)
                     {
                         if(wi2 == e_SrcSelector::A)
                         {
                             iDest->setLineA(i3->getLineA());
                             i3->setLineA(LineRef::invalid);
                             i3->bAEqB = false;
                             i3->bAEqC = false;
                         }
                         else if(wi2 == e_SrcSelector::B)
                         {
                             iDest->setLineB(i3->getLineB());
                             i3->setLineB(LineRef::invalid);
                             i3->bAEqB = false;
                             i3->bBEqC = false;
                         }
                         else if(wi2 == e_SrcSelector::C)
                         {
                             iDest->setLineC(i3->getLineC());
                             i3->setLineC(LineRef::invalid);
                             i3->bBEqC = false;
                             i3->bAEqC = false;
                         }
                     }
 
                     if(missingWinIdx != e_SrcSelector::None)
                     {
                         for(; i3 != end(); ++i3)
                         {
                             e_SrcSelector wi3 = missingWinIdx;
                             if(i3->getLineInFile(wi3).isValid())
                             {
                                 // not found, move the line before iDest
                                 Diff3Line d3l;
                                 if(wi3 == e_SrcSelector::A)
                                 {
                                     if(i3->isEqualAB()) // Stop moving lines up if one equal is found.
                                         break;
                                     d3l.setLineA(i3->getLineA());
                                     i3->setLineA(LineRef::invalid);
                                     i3->bAEqB = false;
                                     i3->bAEqC = false;
                                 }
                                 if(wi3 == e_SrcSelector::B)
                                 {
                                     if(i3->isEqualAB())
                                         break;
                                     d3l.setLineB(i3->getLineB());
                                     i3->setLineB(LineRef::invalid);
                                     i3->bAEqB = false;
                                     i3->bBEqC = false;
                                 }
                                 if(wi3 == e_SrcSelector::C)
                                 {
                                     if(i3->isEqualAC())
                                         break;
                                     d3l.setLineC(i3->getLineC());
                                     i3->setLineC(LineRef::invalid);
                                     i3->bAEqC = false;
                                     i3->bBEqC = false;
                                 }
                                 insert(iDest, d3l);
                             }
                         } // for(), searching for wi3
                     }
                     break;
                 }
             } // for(), searching for wi2
         }     // if, wi found
     }         // for (iMDHL)
 }
 
 // Fourth step
 void Diff3LineList::calcDiff3LineListTrim(
     const std::shared_ptr<LineDataVector> &pldA, const std::shared_ptr<LineDataVector> &pldB, const std::shared_ptr<LineDataVector> &pldC, ManualDiffHelpList* pManualDiffHelpList)
 {
     const Diff3Line d3l_empty;
     remove(d3l_empty);
 
     Diff3LineList::iterator lookAhead = begin();
     Diff3LineList::iterator i3A = begin();
     Diff3LineList::iterator i3B = begin();
     Diff3LineList::iterator i3C = begin();
 
     qint32 line = 0;  // diff3line counters
     qint32 lineA = 0; //
     qint32 lineB = 0;
     qint32 lineC = 0;
 
     ManualDiffHelpList::iterator iMDHL = pManualDiffHelpList->begin();
     // The iterator lookAhead is the variable line look ahead.
     // The iterators i3A, i3B, i3C and corresponding lineA, lineB and lineC stop at empty lines, if found.
     // If possible, then the texts from the look ahead will be moved back to the empty places.
 
     for(; lookAhead != end(); ++lookAhead, ++line)
     {
         if(iMDHL != pManualDiffHelpList->end())
         {
             if((lookAhead->getLineA().isValid() && lookAhead->getLineA() == iMDHL->getLine1(e_SrcSelector::A)) ||
                (lookAhead->getLineB().isValid() && lookAhead->getLineB() == iMDHL->getLine1(e_SrcSelector::B)) ||
                (lookAhead->getLineC().isValid() && lookAhead->getLineC() == iMDHL->getLine1(e_SrcSelector::C)))
             {
                 i3A = lookAhead;
                 i3B = lookAhead;
                 i3C = lookAhead;
                 lineA = line;
                 lineB = line;
                 lineC = line;
                 ++iMDHL;
             }
         }
 
         if(line > lineA && lookAhead->getLineA().isValid() && i3A->getLineB().isValid() && i3A->isEqualBC() &&
            LineData::equal((*pldA)[lookAhead->getLineA()], (*pldB)[i3A->getLineB()]) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineA(), i3A->getLineB(), e_SrcSelector::A, e_SrcSelector::B) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineA(), i3A->getLineC(), e_SrcSelector::A, e_SrcSelector::C))
         {
             // Empty space for A. A matches B and C in the empty line. Move it up.
             i3A->setLineA(lookAhead->getLineA());
             i3A->bAEqB = true;
             i3A->bAEqC = true;
 
             lookAhead->setLineA(LineRef::invalid);
             lookAhead->bAEqB = false;
             lookAhead->bAEqC = false;
             ++i3A;
             ++lineA;
         }
 
         if(line > lineB && lookAhead->getLineB().isValid() && i3B->getLineA().isValid() && i3B->isEqualAC() &&
            LineData::equal((*pldB)[lookAhead->getLineB()], (*pldA)[i3B->getLineA()]) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineB(), i3B->getLineA(), e_SrcSelector::B, e_SrcSelector::A) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineB(), i3B->getLineC(), e_SrcSelector::B, e_SrcSelector::C))
         {
             // Empty space for B. B matches A and C in the empty line. Move it up.
             i3B->setLineB(lookAhead->getLineB());
             i3B->bAEqB = true;
             i3B->bBEqC = true;
             lookAhead->setLineB(LineRef::invalid);
             lookAhead->bAEqB = false;
             lookAhead->bBEqC = false;
             ++i3B;
             ++lineB;
         }
 
         if(line > lineC && lookAhead->getLineC().isValid() && i3C->getLineA().isValid() && i3C->isEqualAB() &&
            LineData::equal((*pldC)[lookAhead->getLineC()], (*pldA)[i3C->getLineA()]) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineC(), i3C->getLineA(), e_SrcSelector::C, e_SrcSelector::A) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineC(), i3C->getLineB(), e_SrcSelector::C, e_SrcSelector::B))
         {
             // Empty space for C. C matches A and B in the empty line. Move it up.
             i3C->setLineC(lookAhead->getLineC());
             i3C->bAEqC = true;
             i3C->bBEqC = true;
             lookAhead->setLineC(LineRef::invalid);
             lookAhead->bAEqC = false;
             lookAhead->bBEqC = false;
             ++i3C;
             ++lineC;
         }
 
         if(line > lineA && lookAhead->getLineA().isValid() && !lookAhead->isEqualAB() && !lookAhead->isEqualAC() &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineA(), i3A->getLineB(), e_SrcSelector::A, e_SrcSelector::B) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineA(), i3A->getLineC(), e_SrcSelector::A, e_SrcSelector::C))
         {
             // Empty space for A. A doesn't match B or C. Move it up.
             i3A->setLineA(lookAhead->getLineA());
             lookAhead->setLineA(LineRef::invalid);
 
             if(i3A->getLineB().isValid() && LineData::equal((*pldA)[i3A->getLineA()], (*pldB)[i3A->getLineB()]))
             {
                 i3A->bAEqB = true;
             }
             if((i3A->isEqualAB() && i3A->isEqualBC()) ||
                (i3A->getLineC().isValid() && LineData::equal((*pldA)[i3A->getLineA()], (*pldC)[i3A->getLineC()])))
             {
                 i3A->bAEqC = true;
             }
 
             ++i3A;
             ++lineA;
         }
 
         if(line > lineB && lookAhead->getLineB().isValid() && !lookAhead->isEqualAB() && !lookAhead->isEqualBC() &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineB(), i3B->getLineA(), e_SrcSelector::B, e_SrcSelector::A) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineB(), i3B->getLineC(), e_SrcSelector::B, e_SrcSelector::C))
         {
             // Empty space for B. B matches neither A nor C. Move B up.
             i3B->setLineB(lookAhead->getLineB());
             lookAhead->setLineB(LineRef::invalid);
 
             if(i3B->getLineA().isValid() && LineData::equal((*pldA)[i3B->getLineA()], (*pldB)[i3B->getLineB()]))
             {
                 i3B->bAEqB = true;
             }
             if((i3B->isEqualAB() && i3B->isEqualAC()) ||
                (i3B->getLineC().isValid() && LineData::equal((*pldB)[i3B->getLineB()], (*pldC)[i3B->getLineC()])))
             {
                 i3B->bBEqC = true;
             }
 
             ++i3B;
             ++lineB;
         }
 
         if(line > lineC && lookAhead->getLineC().isValid() && !lookAhead->isEqualAC() && !lookAhead->isEqualBC() &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineC(), i3C->getLineA(), e_SrcSelector::C, e_SrcSelector::A) &&
            pManualDiffHelpList->isValidMove(lookAhead->getLineC(), i3C->getLineB(), e_SrcSelector::C, e_SrcSelector::B))
         {
             // Empty space for C. C matches neither A nor B. Move C up.
             i3C->setLineC(lookAhead->getLineC());
             lookAhead->setLineC(LineRef::invalid);
 
             if(i3C->getLineA().isValid() && LineData::equal((*pldA)[i3C->getLineA()], (*pldC)[i3C->getLineC()]))
             {
                 i3C->bAEqC = true;
             }
             if((i3C->isEqualAC() && i3C->isEqualAB()) ||
                (i3C->getLineB().isValid() && LineData::equal((*pldB)[i3C->getLineB()], (*pldC)[i3C->getLineC()])))
             {
                 i3C->bBEqC = true;
             }
 
             ++i3C;
             ++lineC;
         }
 
         if(line > lineA && line > lineB && lookAhead->getLineA().isValid() && lookAhead->isEqualAB() && !lookAhead->isEqualAC())
         {
             // Empty space for A and B. A matches B, but not C. Move A & B up.
             Diff3LineList::iterator i = lineA > lineB ? i3A : i3B;
             qint32 l = lineA > lineB ? lineA : lineB;
 
             if(pManualDiffHelpList->isValidMove(i->getLineC(), lookAhead->getLineA(), e_SrcSelector::C, e_SrcSelector::A) &&
                pManualDiffHelpList->isValidMove(i->getLineC(), lookAhead->getLineB(), e_SrcSelector::C, e_SrcSelector::B))
             {
                 i->setLineA(lookAhead->getLineA());
                 i->setLineB(lookAhead->getLineB());
                 i->bAEqB = true;
 
                 if(i->getLineC().isValid() && LineData::equal((*pldA)[i->getLineA()], (*pldC)[i->getLineC()]))
                 {
                     i->bAEqC = true;
                     i->bBEqC = true;
                 }
 
                 lookAhead->setLineA(LineRef::invalid);
                 lookAhead->setLineB(LineRef::invalid);
                 lookAhead->bAEqB = false;
                 i3A = i;
                 i3B = i;
                 ++i3A;
                 ++i3B;
                 lineA = l + 1;
                 lineB = l + 1;
             }
         }
         else if(line > lineA && line > lineC && lookAhead->getLineA().isValid() && lookAhead->isEqualAC() && !lookAhead->isEqualAB())
         {
             // Empty space for A and C. A matches C, but not B. Move A & C up.
             Diff3LineList::iterator i = lineA > lineC ? i3A : i3C;
             qint32 l = lineA > lineC ? lineA : lineC;
 
             if(pManualDiffHelpList->isValidMove(i->getLineB(), lookAhead->getLineA(), e_SrcSelector::B, e_SrcSelector::A) &&
                pManualDiffHelpList->isValidMove(i->getLineB(), lookAhead->getLineC(), e_SrcSelector::B, e_SrcSelector::C))
             {
                 i->setLineA(lookAhead->getLineA());
                 i->setLineC(lookAhead->getLineC());
                 i->bAEqC = true;
 
                 if(i->getLineB().isValid() && LineData::equal((*pldA)[i->getLineA()], (*pldB)[i->getLineB()]))
                 {
                     i->bAEqB = true;
                     i->bBEqC = true;
                 }
 
                 lookAhead->setLineA(LineRef::invalid);
                 lookAhead->setLineC(LineRef::invalid);
                 lookAhead->bAEqC = false;
                 i3A = i;
                 i3C = i;
                 ++i3A;
                 ++i3C;
                 lineA = l + 1;
                 lineC = l + 1;
             }
         }
         else if(line > lineB && line > lineC && lookAhead->getLineB().isValid() && lookAhead->isEqualBC() && !lookAhead->isEqualAC())
         {
             // Empty space for B and C. B matches C, but not A. Move B & C up.
             Diff3LineList::iterator i = lineB > lineC ? i3B : i3C;
             qint32 l = lineB > lineC ? lineB : lineC;
             if(pManualDiffHelpList->isValidMove(i->getLineA(), lookAhead->getLineB(), e_SrcSelector::A, e_SrcSelector::B) &&
                pManualDiffHelpList->isValidMove(i->getLineA(), lookAhead->getLineC(), e_SrcSelector::A, e_SrcSelector::C))
             {
                 i->setLineB(lookAhead->getLineB());
                 i->setLineC(lookAhead->getLineC());
                 i->bBEqC = true;
 
                 if(i->getLineA().isValid() && LineData::equal((*pldA)[i->getLineA()], (*pldB)[i->getLineB()]))
                 {
                     i->bAEqB = true;
                     i->bAEqC = true;
                 }
 
                 lookAhead->setLineB(LineRef::invalid);
                 lookAhead->setLineC(LineRef::invalid);
                 lookAhead->bBEqC = false;
                 i3B = i;
                 i3C = i;
                 ++i3B;
                 ++i3C;
                 lineB = l + 1;
                 lineC = l + 1;
             }
         }
 
         if(lookAhead->getLineA().isValid())
         {
             lineA = line + 1;
             i3A = lookAhead;
             ++i3A;
         }
         if(lookAhead->getLineB().isValid())
         {
             lineB = line + 1;
             i3B = lookAhead;
             ++i3B;
         }
         if(lookAhead->getLineC().isValid())
         {
             lineC = line + 1;
             i3C = lookAhead;
             ++i3C;
         }
     }
 
     remove(d3l_empty);
 
     /*
 
    Diff3LineList::iterator it = d3ll.begin();
    qint32 li=0;
    for( ; it!=d3ll.end(); ++it, ++li )
    {
       printf( "%4d %4d %4d %4d  A%c=B A%c=C B%c=C\n",
          li, it->getLineA(), it->getLineB(), it->getLineC(),
          it->isEqualAB() ? '=' : '!', it->isEqualAC() ? '=' : '!', it->isEqualBC() ? '=' : '!' );
 
    }
 */
 }
 
 void DiffBufferInfo::init(Diff3LineList* pD3ll,
                           const std::shared_ptr<LineDataVector> &pldA, const std::shared_ptr<LineDataVector> &pldB, const std::shared_ptr<LineDataVector> &pldC)
 {
     m_pDiff3LineList = pD3ll;
     mLineDataA = pldA;
     mLineDataB = pldB;
     mLineDataC = pldC;
 }
 
 void Diff3LineList::calcWhiteDiff3Lines(
     const std::shared_ptr<LineDataVector> &pldA, const std::shared_ptr<LineDataVector> &pldB, const std::shared_ptr<LineDataVector> &pldC, const bool bIgnoreComments)
 {
     for(Diff3Line& diff3Line: *this)
     {
         diff3Line.bWhiteLineA = (!diff3Line.getLineA().isValid() || (*pldA)[diff3Line.getLineA()].whiteLine() || (bIgnoreComments && (*pldA)[diff3Line.getLineA()].isPureComment()));
         diff3Line.bWhiteLineB = (!diff3Line.getLineB().isValid() || (*pldB)[diff3Line.getLineB()].whiteLine() || (bIgnoreComments && (*pldB)[diff3Line.getLineB()].isPureComment()));
         diff3Line.bWhiteLineC = (!diff3Line.getLineC().isValid() || (*pldC)[diff3Line.getLineC()].whiteLine() || (bIgnoreComments && (*pldC)[diff3Line.getLineC()].isPureComment()));
     }
 }
 
 // My own diff-invention:
 /*
     Builds DiffList for scratch. Automaticly clears all previous data in list.
 */
 void DiffList::calcDiff(const QString& line1, const QString& line2, const qint32 maxSearchRange)
 {
     clear();
 
     const QChar* p1end = line1.constData() + line1.size();
     const QChar* p2end = line2.constData() + line2.size();
 
     QString::const_iterator p1 = line1.cbegin(), p2 = line2.cbegin();
 
     /*
         This loop should never reach the exit condition specified here. However it must have a hard wired
         stopping point to prevent runaway allocation if something unexpected happens.
         diffList is therefor hard capped at aprox 50 MB in size.
      */
     for(; size() * sizeof(Diff) + sizeof(DiffList) < (50 << 20);)
     {
         qint32 nofEquals = 0;
         while(p1 != line1.cend() && p2 != line2.cend() && *p1 == *p2)
         {
             ++p1;
             ++p2;
             ++nofEquals;
         }
 
         bool bBestValid = false;
         qint32 bestI1 = 0;
         qint32 bestI2 = 0;
         qint32 i1 = 0;
         qint32 i2 = 0;
 
         for(i1 = 0;; ++i1)
         {
             if(&p1[i1] == p1end || (bBestValid && i1 >= bestI1 + bestI2))
             {
                 break;
             }
             for(i2 = 0; i2 < maxSearchRange; ++i2)
             {
                 if (&p2[i2] == p2end || (bBestValid && i1 + i2 >= bestI1 + bestI2))
                 {
                     break;
                 }
                 else if(p2[i2] == p1[i1] &&
                         (abs(i1 - i2) < 3 || (&p2[i2 + 1] == p2end && &p1[i1 + 1] == p1end) ||
                          (&p2[i2 + 1] != p2end && &p1[i1 + 1] != p1end && p2[i2 + 1] == p1[i1 + 1])))
                 {
                     if(i1 + i2 < bestI1 + bestI2 || !bBestValid)
                     {
                         bestI1 = i1;
                         bestI2 = i2;
                         bBestValid = true;
                         break;
                     }
                 }
             }
             /*
                 Bail this should never happen.
                 Acts back stop against harder to detect overfollow issues.
             */
             if(Q_UNLIKELY(i1 == limits<decltype(i1)>::max()))
             {
                 assert(false);
                 throw std::range_error("Too many diffs");
             }
         }
 
         bool bEndReached = false;
         if(bBestValid)
         {
             // The match was found using the strict search. Go back if there are non-strict
             // matches.
             while(bestI1 >= 1 && bestI2 >= 1 && p1[bestI1 - 1] == p2[bestI2 - 1])
             {
                 --bestI1;
                 --bestI2;
             }
             // continue somehow
             Diff d(nofEquals, bestI1, bestI2);
             assert(nofEquals + bestI1 + bestI2 != 0);
             push_back(d);
 
             p1 += bestI1;
             p2 += bestI2;
         }
         else
         {
             // NOTE: Very consitantly entered with p1end == p1 and p2end == p2
             // Nothing else to match.
             Diff d(nofEquals, p1end - p1, p2end - p2);
             push_back(d);
 
             bEndReached = true; //break;
         }
 
         // Sometimes the algorithm that chooses the first match unfortunately chooses
         // a match where later actually equal parts don't match anymore.
         // A different match could be achieved, if we start at the end.
         // Do it, if it would be a better match.
         qint32 nofUnmatched = 0;
         QString::const_iterator pu1 = p1 - 1;
         QString::const_iterator pu2 = p2 - 1;
 
         while(pu1 >= line1.begin() && pu2 >= line2.begin() && *pu1 == *pu2)
         {
             ++nofUnmatched;
             --pu1;
             --pu2;
         }
 
         if(nofUnmatched > 0)
         {
             // We want to go backwards the nofUnmatched elements and redo
             // the matching
             Diff d = back();
             const Diff origBack = d;
             pop_back();
 
             while(nofUnmatched > 0)
             {
                 if(d.diff1() > 0 && d.diff2() > 0)
                 {
                     d.adjustDiff1(-1);
                     d.adjustDiff2(-1);
                     --nofUnmatched;
                 }
                 else if(d.numberOfEquals() > 0)
                 {
                     d.adjustNumberOfEquals(-1);
                     --nofUnmatched;
                 }
 
                 if(d.numberOfEquals() == 0 && (d.diff1() == 0 || d.diff2() == 0) && nofUnmatched > 0)
                 {
                     if(empty())
                         break;
                     d.adjustNumberOfEquals(back().numberOfEquals());
                     d.adjustDiff1(back().diff1());
                     d.adjustDiff2(back().diff2());
                     pop_back();
                     bEndReached = false;
                 }
             }
 
             if(bEndReached)
                 push_back(origBack);
             else
             {
 
                 p1 = pu1 + 1 + nofUnmatched;
                 p2 = pu2 + 1 + nofUnmatched;
                 push_back(d);
             }
         }
         if(bEndReached)
             break;
     }
 
     assert(size() * sizeof(Diff) + sizeof(DiffList) <= (50 << 20));
 
 #ifndef NDEBUG
     // Verify difflist
     {
 
         qint32 l1 = 0;
         qint32 l2 = 0;
 
         for(const Diff& theDiff: *this)
         {
             l1 += (theDiff.numberOfEquals() + theDiff.diff1());
             l2 += (theDiff.numberOfEquals() + theDiff.diff2());
         }
 
         assert(l1 == line1.size() && l2 == line2.size());
     }
 #endif // !NDEBUG
 }
 //Compute fineDiff
 void DiffList::optimize()
 {
     DiffList::iterator dli;
     bool bUsefulFineDiff = false;
     qint64 index = 0;
 
     for(const Diff& diff: *this)
     {
         if(diff.numberOfEquals() >= 4)
         {
             bUsefulFineDiff = true;
             break;
         }
     }
 
     for(Diff& diff: *this)
     {
         if(!bUsefulFineDiff || index <= 0)
             diff.refine();
 
         ++index;
     }
 }
 
 bool Diff3Line::fineDiff(bool inBTextsTotalEqual, const e_SrcSelector selector, const std::shared_ptr<LineDataVector> &v1, const std::shared_ptr<LineDataVector> &v2, const IgnoreFlags eIgnoreFlags)
 {
     LineRef k1 = 0;
     LineRef k2 = 0;
     qint32 maxSearchLength = 500;
     bool bTextsTotalEqual = inBTextsTotalEqual;
     bool bIgnoreComments = eIgnoreFlags & IgnoreFlag::ignoreComments;
     bool bIgnoreWhiteSpace = eIgnoreFlags & IgnoreFlag::ignoreWhiteSpace;
 
     assert(selector == e_SrcSelector::A || selector == e_SrcSelector::B || selector == e_SrcSelector::C);
 
     if(selector == e_SrcSelector::A)
     {
         k1 = getLineA();
         k2 = getLineB();
     }
     else if(selector == e_SrcSelector::B)
     {
         k1 = getLineB();
         k2 = getLineC();
     }
     else if(selector == e_SrcSelector::C)
     {
         k1 = getLineC();
         k2 = getLineA();
     }
 
     qCDebug(kdiffCore) << "k1 = " << k1 << ", k2 = " << k2;
     if((!k1.isValid() && k2.isValid()) || (k1.isValid() && !k2.isValid())) bTextsTotalEqual = false;
     if(k1.isValid() && k2.isValid())
     {
         assert(((unsigned long)k1) <= (*v1).size() && (*v1)[k1].getBuffer() != nullptr);
         assert(((unsigned long)k2) <= (*v2).size() && (*v2)[k2].getBuffer() != nullptr);
 
         if((*v1)[k1].size() != (*v2)[k2].size() || QString::compare((*v1)[k1].getLine(), (*v2)[k2].getLine()) != 0)
         {
             bTextsTotalEqual = false;
             auto pDiffList = std::make_shared<DiffList>();
             pDiffList->calcDiff((*v1)[k1].getLine(), (*v2)[k2].getLine(), maxSearchLength);
 
             // Optimize the diff list.
             pDiffList->optimize();
             setFineDiff(selector, pDiffList);
         }
         /*
             Override default euality for white lines and comments.
         */
         if(((bIgnoreComments && (*v1)[k1].isSkipable()) || (bIgnoreWhiteSpace && (*v1)[k1].whiteLine())) && ((bIgnoreComments && (*v2)[k2].isSkipable()) || (bIgnoreWhiteSpace && (*v2)[k2].whiteLine())))
         {
             if(selector == e_SrcSelector::A)
             {
                 bAEqB = true;
             }
             else if(selector == e_SrcSelector::B)
             {
                 bBEqC = true;
             }
             else if(selector == e_SrcSelector::C)
             {
                 bAEqC = true;
             }
         }
     }
 
     return bTextsTotalEqual;
 }
 
 void Diff3Line::getLineInfo(const e_SrcSelector winIdx, const bool isTriple, LineRef& lineIdx,
                             std::shared_ptr<const DiffList>& pFineDiff1, std::shared_ptr<const DiffList>& pFineDiff2, // return values
                             ChangeFlags& changed, ChangeFlags& changed2) const
 {
     changed = NoChange;
     changed2 = NoChange;
     bool bAEqualB = this->isEqualAB() || (bWhiteLineA && bWhiteLineB);
     bool bAEqualC = this->isEqualAC() || (bWhiteLineA && bWhiteLineC);
     bool bBEqualC = this->isEqualBC() || (bWhiteLineB && bWhiteLineC);
 
     assert(winIdx >= e_SrcSelector::A && winIdx <= e_SrcSelector::C);
     if(winIdx == e_SrcSelector::A)
     {
         lineIdx = getLineA();
         pFineDiff1 = pFineAB;
         pFineDiff2 = pFineCA;
 
         changed = ((!getLineB().isValid()) != (!lineIdx.isValid()) ? AChanged : NoChange) |
                    ((!getLineC().isValid()) != (!lineIdx.isValid()) && isTriple ? BChanged : NoChange);
         changed2 = (bAEqualB ? NoChange : AChanged) | (bAEqualC || !isTriple ? NoChange : BChanged);
     }
     else if(winIdx == e_SrcSelector::B)
     {
         lineIdx = getLineB();
         pFineDiff1 = pFineBC;
         pFineDiff2 = pFineAB;
         changed = ((!getLineC().isValid()) != (!lineIdx.isValid()) && isTriple ? AChanged : NoChange) |
                    ((!getLineA().isValid()) != (!lineIdx.isValid()) ? BChanged : NoChange);
         changed2 = (bBEqualC || !isTriple ? NoChange : AChanged) | (bAEqualB ? NoChange : BChanged);
     }
     else if(winIdx == e_SrcSelector::C)
     {
         lineIdx = getLineC();
         pFineDiff1 = pFineCA;
         pFineDiff2 = pFineBC;
         changed = ((!getLineA().isValid()) != (!lineIdx.isValid()) ? AChanged : NoChange) |
                    ((!getLineB().isValid()) != (!lineIdx.isValid()) ? BChanged : NoChange);
         changed2 = (bAEqualC ? NoChange : AChanged) | (bBEqualC ? NoChange : BChanged);
     }
 }
 
 bool Diff3LineList::fineDiff(const e_SrcSelector selector, const std::shared_ptr<LineDataVector> &v1, const std::shared_ptr<LineDataVector> &v2, const IgnoreFlags eIgnoreFlags)
 {
     // Finetuning: Diff each line with deltas
     ProgressScope pp;
     bool bTextsTotalEqual = true;
     size_t listSize = size();
     ProgressProxy::setMaxNofSteps(listSize);
 
     for(Diff3Line &diff: *this)
     {
         bTextsTotalEqual = diff.fineDiff(bTextsTotalEqual, selector, v1, v2, eIgnoreFlags);
         ProgressProxy::step();
     }
     return bTextsTotalEqual;
 }
 
 // Convert the list to a vector of pointers
 void Diff3LineList::calcDiff3LineVector(Diff3LineVector& d3lv)
 {
     d3lv.resize(SafeInt<QtSizeType>(size()));
     Diff3LineList::iterator i;
     QtSizeType j = 0;
     for(i = begin(); i != end(); ++i, ++j)
     {
         d3lv[j] = &(*i);
     }
     assert(j == d3lv.size());
 }
 
 // Just make sure that all input lines are in the output too, exactly once.
 void Diff3LineList::debugLineCheck(const LineType size, const e_SrcSelector srcSelector) const
 {
     //FIXME:Does not work when m_pOptions->m_bDiff3AlignBC is set.
     LineType i = 0;
 
     for(const Diff3Line &entry: *this)
     {
         LineRef line;
 
         assert(srcSelector == e_SrcSelector::A || srcSelector == e_SrcSelector::B || srcSelector == e_SrcSelector::C);
         if(srcSelector == e_SrcSelector::A)
             line = entry.getLineA();
         else if(srcSelector == e_SrcSelector::B)
             line = entry.getLineB();
         else if(srcSelector == e_SrcSelector::C)
             line = entry.getLineC();
 
         if(line.isValid())
         {
             if(line != i)
             {
                 #ifndef AUTOTEST
                 KMessageBox::error(nullptr, i18n("Data loss error:\n"
                                                  "If it is reproducible please contact the author.\n"),
                                    i18n("Severe Internal Error"));
                 #endif
 
                 qCCritical(kdiffMain) << "Severe Internal Error." << " line != i for srcSelector=" << (qint32)srcSelector << "\n";
                 ::exit(-1);
             }
             ++i;
         }
     }
 
     if(size != i)
     {
         #ifndef AUTOTEST
         KMessageBox::error(nullptr, i18n(
                                   "Data loss error:\n"
                                   "If it is reproducible please contact the author.\n"),
                            i18n("Severe Internal Error"));
         #endif
 
         qCCritical(kdiffMain) << "Severe Internal Error.: " << size << " != " << i << "\n";
         ::exit(-1);
     }
 }
 
 void Diff3LineList::findHistoryRange(const QRegularExpression& historyStart, bool bThreeFiles, HistoryRange& range) const
 {
     QString historyLead;
     // Search for start of history
     for(range.start = begin(), range.startIdx = 0; range.start != end(); ++range.start, ++range.startIdx)
     {
         if(historyStart.match(range.start->getString(e_SrcSelector::A)).hasMatch() &&
            historyStart.match(range.start->getString(e_SrcSelector::B)).hasMatch() &&
            (!bThreeFiles || historyStart.match(range.start->getString(e_SrcSelector::C)).hasMatch()))
         {
             historyLead = Utils::calcHistoryLead(range.start->getString(e_SrcSelector::A));
             break;
         }
     }
     // Search for end of history
     for(range.end = range.start, range.endIdx = range.startIdx; range.end != end(); ++range.end, ++range.endIdx)
     {
         const QString sA = range.end->getString(e_SrcSelector::A);
         const QString sB = range.end->getString(e_SrcSelector::B);
         const QString sC = range.end->getString(e_SrcSelector::C);
         if((!sA.isEmpty() && historyLead != Utils::calcHistoryLead(sA)) ||
            (!sB.isEmpty() && historyLead != Utils::calcHistoryLead(sB)) ||
            (bThreeFiles && !sC.isEmpty() && historyLead != Utils::calcHistoryLead(sC)))
         {
             break; // End of the history
         }
     }
 }
 
 void Diff3LineList::dump()
 {
     QTextStream out(stdout);
     quint32 i = 1;
     out << "---begin----\n";
     for(const Diff3Line &diffRec : *this)
     {
         out << "line = " << i<< "\n";
         out << "lineA = " << diffRec.getLineA()<< "\n";
         out << "lineB = " << diffRec.getLineB()<< "\n";
         out << "lineC = " << diffRec.getLineC()<< "\n";
 
         out << "isEqualAB = " << diffRec.isEqualAB()<< "\n";
         out << "isEqualAC = " << diffRec.isEqualAC()<< "\n";
         out << "isEqualBC = " << diffRec.isEqualBC()<< "\n";
         ++i;
     }
 
     out << "---end----\n";
 }