1 files changed, 33 insertions, 9 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index 674064e..7d5fa43 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -74,6 +74,8 @@ static inline QFixed leadingSpaceWidth(QTextEngine *eng, const QScriptLine &line
 
     int pos = line.length;
     const HB_CharAttributes *attributes = eng->attributes();
+    if (!attributes)
+        return QFixed();
     while (pos > 0 && attributes[line.from + pos - 1].whiteSpace)
         --pos;
     return eng->width(line.from + pos, line.length - pos);
@@ -601,7 +603,7 @@ bool QTextLayout::cacheEnabled() const
 void QTextLayout::beginLayout()
 {
 #ifndef QT_NO_DEBUG
-    if (d->layoutData && d->layoutData->inLayout) {
+    if (d->layoutData && d->layoutData->layoutState == QTextEngine::InLayout) {
         qWarning("QTextLayout::beginLayout: Called while already doing layout");
         return;
     }
@@ -609,7 +611,7 @@ void QTextLayout::beginLayout()
     d->invalidate();
     d->clearLineData();
     d->itemize();
-    d->layoutData->inLayout = true;
+    d->layoutData->layoutState = QTextEngine::InLayout;
 }
 
 /*!
@@ -618,7 +620,7 @@ void QTextLayout::beginLayout()
 void QTextLayout::endLayout()
 {
 #ifndef QT_NO_DEBUG
-    if (!d->layoutData || !d->layoutData->inLayout) {
+    if (!d->layoutData || d->layoutData->layoutState == QTextEngine::LayoutEmpty) {
         qWarning("QTextLayout::endLayout: Called without beginLayout()");
         return;
     }
@@ -627,7 +629,7 @@ void QTextLayout::endLayout()
     if (l && d->lines.at(l-1).length < 0) {
         QTextLine(l-1, d).setNumColumns(INT_MAX);
     }
-    d->layoutData->inLayout = false;
+    d->layoutData->layoutState = QTextEngine::LayoutEmpty;
     if (!d->cacheGlyphs)
         d->freeMemory();
 }
@@ -757,11 +759,14 @@ bool QTextLayout::isValidCursorPosition(int pos) const
 QTextLine QTextLayout::createLine()
 {
 #ifndef QT_NO_DEBUG
-    if (!d->layoutData || !d->layoutData->inLayout) {
+    if (!d->layoutData || d->layoutData->layoutState == QTextEngine::LayoutEmpty) {
         qWarning("QTextLayout::createLine: Called without layouting");
         return QTextLine();
     }
 #endif
+    if (d->layoutData->layoutState == QTextEngine::LayoutFailed)
+        return QTextLine();
+
     int l = d->lines.size();
     if (l && d->lines.at(l-1).length < 0) {
         QTextLine(l-1, d).setNumColumns(INT_MAX);
@@ -1704,14 +1709,18 @@ namespace {
             return glyphs.glyphs[logClusters[currentPosition - 1]];
         }
 
+        inline void adjustRightBearing(glyph_t glyph)
+        {
+            qreal rb;
+            fontEngine->getGlyphBearings(glyph, 0, &rb);
+            rightBearing = qMin(QFixed(), QFixed::fromReal(rb));
+        }
+
         inline void adjustRightBearing()
         {
             if (currentPosition <= 0)
                 return;
-
-            qreal rb;
-            fontEngine->getGlyphBearings(currentGlyph(), 0, &rb);
-            rightBearing = qMin(QFixed(), QFixed::fromReal(rb));
+            adjustRightBearing(currentGlyph());
         }
 
         inline void resetRightBearing()
@@ -1801,6 +1810,8 @@ void QTextLine::layout_helper(int maxGlyphs)
     Qt::Alignment alignment = eng->option.alignment();
 
     const HB_CharAttributes *attributes = eng->attributes();
+    if (!attributes)
+        return;
     lbh.currentPosition = line.from;
     int end = 0;
     lbh.logClusters = eng->layoutData->logClustersPtr;
@@ -1814,6 +1825,8 @@ void QTextLine::layout_helper(int maxGlyphs)
             if (!current.num_glyphs) {
                 eng->shape(item);
                 attributes = eng->attributes();
+                if (!attributes)
+                    return;
                 lbh.logClusters = eng->layoutData->logClustersPtr;
             }
             lbh.currentPosition = qMax(line.from, current.position);
@@ -1892,6 +1905,9 @@ void QTextLine::layout_helper(int maxGlyphs)
         } else {
             lbh.whiteSpaceOrObject = false;
             bool sb_or_ws = false;
+            glyph_t previousGlyph = 0;
+            if (lbh.currentPosition > 0 && lbh.logClusters[lbh.currentPosition - 1] <lbh.glyphs.numGlyphs)
+                previousGlyph = lbh.currentGlyph(); // needed to calculate right bearing later
             do {
                 addNextCluster(lbh.currentPosition, end, lbh.tmpData, lbh.glyphCount,
                                current, lbh.logClusters, lbh.glyphs);
@@ -1935,9 +1951,17 @@ void QTextLine::layout_helper(int maxGlyphs)
             // We ignore the right bearing if the minimum negative bearing is too little to
             // expand the text beyond the edge.
             if (sb_or_ws|breakany) {
+                QFixed rightBearing = lbh.rightBearing; // store previous right bearing
+#if !defined(Q_WS_MAC)
                 if (lbh.calculateNewWidth(line) - lbh.minimumRightBearing > line.width)
+#endif
                     lbh.adjustRightBearing();
                 if (lbh.checkFullOtherwiseExtend(line)) {
+                    // we are too wide, fix right bearing
+                    if (rightBearing <= 0)
+                        lbh.rightBearing = rightBearing; // take from cache
+                    else if (previousGlyph > 0)
+                        lbh.adjustRightBearing(previousGlyph);
                     if (!breakany) {
                         line.textWidth += lbh.softHyphenWidth;
                     }