diff options
Diffstat (limited to 'src/gui/text/qfontengine.cpp')
| -rw-r--r-- | src/gui/text/qfontengine.cpp | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp index 10d3b5d2cb..80c28a376a 100644 --- a/src/gui/text/qfontengine.cpp +++ b/src/gui/text/qfontengine.cpp @@ -436,6 +436,10 @@ bool QFontEngine::processHheaTable() const qint16 descent = qFromBigEndian<qint16>(hhea.constData() + 6); qint16 leading = qFromBigEndian<qint16>(hhea.constData() + 8); + // Some fonts may have invalid HHEA data. We detect this and bail out. + if (ascent == 0 && descent == 0) + return false; + QFixed unitsPerEm = emSquareSize(); m_ascent = QFixed::fromReal(ascent * fontDef.pixelSize) / unitsPerEm; m_descent = -QFixed::fromReal(descent * fontDef.pixelSize) / unitsPerEm; @@ -450,7 +454,10 @@ bool QFontEngine::processHheaTable() const void QFontEngine::initializeHeightMetrics() const { - bool hasEmbeddedBitmaps = !getSfntTable(MAKE_TAG('E', 'B', 'L', 'C')).isEmpty() || !getSfntTable(MAKE_TAG('C', 'B', 'L', 'C')).isEmpty(); + bool hasEmbeddedBitmaps = + !getSfntTable(MAKE_TAG('E', 'B', 'L', 'C')).isEmpty() + || !getSfntTable(MAKE_TAG('C', 'B', 'L', 'C')).isEmpty() + || !getSfntTable(MAKE_TAG('b', 'd', 'a', 't')).isEmpty(); if (!hasEmbeddedBitmaps) { // Get HHEA table values if available processHheaTable(); @@ -476,10 +483,16 @@ bool QFontEngine::processOS2Table() const enum { USE_TYPO_METRICS = 0x80 }; QFixed unitsPerEm = emSquareSize(); if (fsSelection & USE_TYPO_METRICS) { + // Some fonts may have invalid OS/2 data. We detect this and bail out. + if (typoAscent == 0 && typoDescent == 0) + return false; m_ascent = QFixed::fromReal(typoAscent * fontDef.pixelSize) / unitsPerEm; m_descent = -QFixed::fromReal(typoDescent * fontDef.pixelSize) / unitsPerEm; m_leading = QFixed::fromReal(typoLineGap * fontDef.pixelSize) / unitsPerEm; } else { + // Some fonts may have invalid OS/2 data. We detect this and bail out. + if (winAscent == 0 && winDescent == 0) + return false; m_ascent = QFixed::fromReal(winAscent * fontDef.pixelSize) / unitsPerEm; m_descent = QFixed::fromReal(winDescent * fontDef.pixelSize) / unitsPerEm; } |