Always use QExplicitlySharedDataPointer<QFontPrivate>

Fixes a refcount bug that occurs when QFont is constructed from a
QFontPrivate* that was created without an initial ref().

Merge-request: 1831
Reviewed-by: Olivier Goffart <ogoffart@trolltech.com>

4 files changed, 32 insertions, 37 deletions

diff --git a/src/gui/text/qfont.cpp b/src/gui/text/qfont.cpp
index 1285935..8722f5b 100644
--- a/src/gui/text/qfont.cpp
+++ b/src/gui/text/qfont.cpp
@@ -2324,22 +2324,22 @@ QDataStream &operator>>(QDataStream &s, QFont &font)
 */
 QFontInfo::QFontInfo(const QFont &font)
     : d(font.d.data())
-{ d->ref.ref(); }
+{
+}
 
 /*!
     Constructs a copy of \a fi.
 */
 QFontInfo::QFontInfo(const QFontInfo &fi)
-    : d(fi.d)
-{ d->ref.ref(); }
+    : d(fi.d.data())
+{
+}
 
 /*!
     Destroys the font info object.
 */
 QFontInfo::~QFontInfo()
 {
-    if (!d->ref.deref())
-        delete d;
 }
 
 /*!
@@ -2347,7 +2347,7 @@ QFontInfo::~QFontInfo()
 */
 QFontInfo &QFontInfo::operator=(const QFontInfo &fi)
 {
-    qAtomicAssign(d, fi.d);
+    d = fi.d.data();
     return *this;
 }
 
diff --git a/src/gui/text/qfontinfo.h b/src/gui/text/qfontinfo.h
index 335d761..0998949 100644
--- a/src/gui/text/qfontinfo.h
+++ b/src/gui/text/qfontinfo.h
@@ -43,6 +43,7 @@
 #define QFONTINFO_H
 
 #include <QtGui/qfont.h>
+#include <QtCore/qsharedpointer.h>
 
 QT_BEGIN_HEADER
 
@@ -77,7 +78,7 @@ public:
     bool exactMatch() const;
 
 private:
-    QFontPrivate *d;
+    QExplicitlySharedDataPointer<QFontPrivate> d;
 };
 
 QT_END_NAMESPACE
diff --git a/src/gui/text/qfontmetrics.cpp b/src/gui/text/qfontmetrics.cpp
index ce122aa..b8c1b33 100644
--- a/src/gui/text/qfontmetrics.cpp
+++ b/src/gui/text/qfontmetrics.cpp
@@ -165,7 +165,6 @@ extern int qt_defaultDpi();
 QFontMetrics::QFontMetrics(const QFont &font)
     : d(font.d.data())
 {
-    d->ref.ref();
 }
 
 /*!
@@ -196,7 +195,6 @@ QFontMetrics::QFontMetrics(const QFont &font, QPaintDevice *paintdevice)
         d->screen = screen;
     } else {
         d = font.d.data();
-        d->ref.ref();
     }
 
 }
@@ -205,8 +203,9 @@ QFontMetrics::QFontMetrics(const QFont &font, QPaintDevice *paintdevice)
     Constructs a copy of \a fm.
 */
 QFontMetrics::QFontMetrics(const QFontMetrics &fm)
-    : d(fm.d)
-{ d->ref.ref(); }
+    : d(fm.d.data())
+{
+}
 
 /*!
     Destroys the font metrics object and frees all allocated
@@ -214,8 +213,6 @@ QFontMetrics::QFontMetrics(const QFontMetrics &fm)
 */
 QFontMetrics::~QFontMetrics()
 {
-    if (!d->ref.deref())
-        delete d;
 }
 
 /*!
@@ -223,7 +220,7 @@ QFontMetrics::~QFontMetrics()
 */
 QFontMetrics &QFontMetrics::operator=(const QFontMetrics &fm)
 {
-    qAtomicAssign(d, fm.d);
+    d = fm.d.data();
     return *this;
 }
 
@@ -536,7 +533,7 @@ int QFontMetrics::width(const QString &text, int len) const
     if (len == 0)
         return 0;
 
-    QTextEngine layout(text, d);
+    QTextEngine layout(text, d.data());
     layout.ignoreBidi = true;
     return qRound(layout.width(0, len));
 }
@@ -612,7 +609,7 @@ int QFontMetrics::charWidth(const QString &text, int pos) const
         int from = qMax(0, pos - 8);
         int to = qMin(text.length(), pos + 8);
         QString cstr = QString::fromRawData(text.unicode() + from, to - from);
-        QTextEngine layout(cstr, d);
+        QTextEngine layout(cstr, d.data());
         layout.ignoreBidi = true;
         layout.itemize();
         width = qRound(layout.width(pos-from, 1));
@@ -661,7 +658,7 @@ QRect QFontMetrics::boundingRect(const QString &text) const
     if (text.length() == 0)
         return QRect();
 
-    QTextEngine layout(text, d);
+    QTextEngine layout(text, d.data());
     layout.ignoreBidi = true;
     layout.itemize();
     glyph_metrics_t gm = layout.boundingBox(0, text.length());
@@ -770,7 +767,7 @@ QRect QFontMetrics::boundingRect(const QRect &rect, int flags, const QString &te
 
     QRectF rb;
     QRectF rr(rect);
-    qt_format_text(QFont(d), rr, flags | Qt::TextDontPrint, text, &rb, tabStops, tabArray,
+    qt_format_text(QFont(d.data()), rr, flags | Qt::TextDontPrint, text, &rb, tabStops, tabArray,
                    tabArrayLen, 0);
 
     return rb.toAlignedRect();
@@ -831,7 +828,7 @@ QRect QFontMetrics::tightBoundingRect(const QString &text) const
     if (text.length() == 0)
         return QRect();
 
-    QTextEngine layout(text, d);
+    QTextEngine layout(text, d.data());
     layout.ignoreBidi = true;
     layout.itemize();
     glyph_metrics_t gm = layout.tightBoundingBox(0, text.length());
@@ -876,7 +873,7 @@ QString QFontMetrics::elidedText(const QString &text, Qt::TextElideMode mode, in
         }
         _text = _text.mid(posA);
     }
-    QStackTextEngine engine(_text, QFont(d));
+    QStackTextEngine engine(_text, QFont(d.data()));
     return engine.elidedText(mode, width, flags);
 }
 
@@ -989,9 +986,8 @@ int QFontMetrics::lineWidth() const
     from the given \a fontMetrics object.
 */
 QFontMetricsF::QFontMetricsF(const QFontMetrics &fontMetrics)
-    : d(fontMetrics.d)
+    : d(fontMetrics.d.data())
 {
-    d->ref.ref();
 }
 
 /*!
@@ -1001,7 +997,7 @@ QFontMetricsF::QFontMetricsF(const QFontMetrics &fontMetrics)
 */
 QFontMetricsF &QFontMetricsF::operator=(const QFontMetrics &other)
 {
-    qAtomicAssign(d, other.d);
+    d = other.d.data();
     return *this;
 }
 
@@ -1021,7 +1017,6 @@ QFontMetricsF &QFontMetricsF::operator=(const QFontMetrics &other)
 QFontMetricsF::QFontMetricsF(const QFont &font)
     : d(font.d.data())
 {
-    d->ref.ref();
 }
 
 /*!
@@ -1052,7 +1047,6 @@ QFontMetricsF::QFontMetricsF(const QFont &font, QPaintDevice *paintdevice)
         d->screen = screen;
     } else {
         d = font.d.data();
-        d->ref.ref();
     }
 
 }
@@ -1061,8 +1055,9 @@ QFontMetricsF::QFontMetricsF(const QFont &font, QPaintDevice *paintdevice)
     Constructs a copy of \a fm.
 */
 QFontMetricsF::QFontMetricsF(const QFontMetricsF &fm)
-    : d(fm.d)
-{ d->ref.ref(); }
+    : d(fm.d.data())
+{
+}
 
 /*!
     Destroys the font metrics object and frees all allocated
@@ -1070,8 +1065,6 @@ QFontMetricsF::QFontMetricsF(const QFontMetricsF &fm)
 */
 QFontMetricsF::~QFontMetricsF()
 {
-    if (!d->ref.deref())
-        delete d;
 }
 
 /*!
@@ -1079,7 +1072,7 @@ QFontMetricsF::~QFontMetricsF()
 */
 QFontMetricsF &QFontMetricsF::operator=(const QFontMetricsF &fm)
 {
-    qAtomicAssign(d, fm.d);
+    d = fm.d.data();
     return *this;
 }
 
@@ -1374,7 +1367,7 @@ qreal QFontMetricsF::rightBearing(QChar ch) const
 */
 qreal QFontMetricsF::width(const QString &text) const
 {
-    QTextEngine layout(text, d);
+    QTextEngine layout(text, d.data());
     layout.ignoreBidi = true;
     layout.itemize();
     return layout.width(0, text.length()).toReal();
@@ -1451,7 +1444,7 @@ QRectF QFontMetricsF::boundingRect(const QString &text) const
     if (len == 0)
         return QRectF();
 
-    QTextEngine layout(text, d);
+    QTextEngine layout(text, d.data());
     layout.ignoreBidi = true;
     layout.itemize();
     glyph_metrics_t gm = layout.boundingBox(0, len);
@@ -1559,7 +1552,7 @@ QRectF QFontMetricsF::boundingRect(const QRectF &rect, int flags, const QString&
             tabArrayLen++;
 
     QRectF rb;
-    qt_format_text(QFont(d), rect, flags | Qt::TextDontPrint, text, &rb, tabStops, tabArray,
+    qt_format_text(QFont(d.data()), rect, flags | Qt::TextDontPrint, text, &rb, tabStops, tabArray,
                    tabArrayLen, 0);
     return rb;
 }
@@ -1624,7 +1617,7 @@ QRectF QFontMetricsF::tightBoundingRect(const QString &text) const
     if (text.length() == 0)
         return QRect();
 
-    QTextEngine layout(text, d);
+    QTextEngine layout(text, d.data());
     layout.ignoreBidi = true;
     layout.itemize();
     glyph_metrics_t gm = layout.tightBoundingBox(0, text.length());
@@ -1649,7 +1642,7 @@ QRectF QFontMetricsF::tightBoundingRect(const QString &text) const
 */
 QString QFontMetricsF::elidedText(const QString &text, Qt::TextElideMode mode, qreal width, int flags) const
 {
-    QStackTextEngine engine(text, QFont(d));
+    QStackTextEngine engine(text, QFont(d.data()));
     return engine.elidedText(mode, QFixed::fromReal(width), flags);
 }
 
diff --git a/src/gui/text/qfontmetrics.h b/src/gui/text/qfontmetrics.h
index 1147e3a..23200c5 100644
--- a/src/gui/text/qfontmetrics.h
+++ b/src/gui/text/qfontmetrics.h
@@ -43,6 +43,7 @@
 #define QFONTMETRICS_H
 
 #include <QtGui/qfont.h>
+#include <QtCore/qsharedpointer.h>
 #ifndef QT_INCLUDE_COMPAT
 #include <QtCore/qrect.h>
 #endif
@@ -131,7 +132,7 @@ private:
     friend class QFontMetricsF;
     friend class QStackTextEngine;
 
-    QFontPrivate *d;
+    QExplicitlySharedDataPointer<QFontPrivate> d;
 };
 
 
@@ -187,7 +188,7 @@ public:
     inline bool operator !=(const QFontMetricsF &other) const { return !operator==(other); }
 
 private:
-    QFontPrivate *d;
+    QExplicitlySharedDataPointer<QFontPrivate> d;
 };
 
 QT_END_NAMESPACE