diff options
| -rw-r--r-- | src/corelib/io/qdatastream.cpp | 6 | ||||
| -rw-r--r-- | tests/auto/corelib/io/qdatastream/tst_qdatastream.cpp | 44 |
2 files changed, 49 insertions, 1 deletions
diff --git a/src/corelib/io/qdatastream.cpp b/src/corelib/io/qdatastream.cpp index 9a71f60854..5e5e155534 100644 --- a/src/corelib/io/qdatastream.cpp +++ b/src/corelib/io/qdatastream.cpp @@ -1046,8 +1046,12 @@ QDataStream &QDataStream::operator<<(float f) } x; x.val1 = g; x.val2 = qbswap(x.val2); - g = x.val1; + + if (dev->write((char *)&x.val2, sizeof(float)) != sizeof(float)) + q_status = WriteFailed; + return *this; } + if (dev->write((char *)&g, sizeof(float)) != sizeof(float)) q_status = WriteFailed; return *this; diff --git a/tests/auto/corelib/io/qdatastream/tst_qdatastream.cpp b/tests/auto/corelib/io/qdatastream/tst_qdatastream.cpp index ef384f86cd..f999f44670 100644 --- a/tests/auto/corelib/io/qdatastream/tst_qdatastream.cpp +++ b/tests/auto/corelib/io/qdatastream/tst_qdatastream.cpp @@ -195,6 +195,8 @@ private slots: void compatibility_Qt3(); void compatibility_Qt2(); + void floatingPointNaN(); + private: void writebool(QDataStream *s); void writeQBitArray(QDataStream *s); @@ -3102,6 +3104,48 @@ void tst_QDataStream::compatibility_Qt2() QVERIFY(in_palette.color(QPalette::Light) == Qt::green); } +void tst_QDataStream::floatingPointNaN() +{ + QDataStream::ByteOrder bo = QSysInfo::ByteOrder == QSysInfo::BigEndian + ? QDataStream::LittleEndian + : QDataStream::BigEndian; + + // Test and verify that values that become (s)nan's after swapping endianness + // don't change in the process. + // When compiling with e.g., MSVC (32bit) and when the fpu is used (fp:precise) + // all snan's will be converted to qnan's (default behavior). + // IF we get a snan after swapping endianness we can not copy the value to another + // float as this will cause the value to differ from the original value. + QByteArray ba; + + union { + float f; + quint32 i; + } xs[2]; + + xs[0].i = qbswap<quint32>(0xff800001); + xs[1].i = qbswap<quint32>(0x7f800001); + + { + QDataStream stream(&ba, QIODevice::WriteOnly); + stream.setByteOrder(bo); + stream.setFloatingPointPrecision(QDataStream::SinglePrecision); + stream << xs[0].f; + stream << xs[1].f; + } + + { + QDataStream stream(ba); + stream.setByteOrder(bo); + stream.setFloatingPointPrecision(QDataStream::SinglePrecision); + float fr = 0.0f; + stream >> fr; + QCOMPARE(fr, xs[0].f); + stream >> fr; + QCOMPARE(fr, xs[1].f); + } +} + void tst_QDataStream::floatingPointPrecision() { QByteArray ba; |