add error handling to QXmlStreamWriter

introduce QXmlStreamWriter::hasError(). set the error flag when any
write error occurs. ignore subsequent writes after the first error.

Reviewed-by: denis

1 files changed, 82 insertions, 0 deletions

diff --git a/tests/auto/qxmlstream/tst_qxmlstream.cpp b/tests/auto/qxmlstream/tst_qxmlstream.cpp
index 19e4b90..9e4f3ec 100644
--- a/tests/auto/qxmlstream/tst_qxmlstream.cpp
+++ b/tests/auto/qxmlstream/tst_qxmlstream.cpp
@@ -574,6 +574,7 @@ private slots:
     void checkCommentIndentation() const;
     void checkCommentIndentation_data() const;
     void qtbug9196_crash() const;
+    void hasError() const;
 
 private:
     static QByteArray readFile(const QString &filename);
@@ -1560,5 +1561,86 @@ void tst_QXmlStream::qtbug9196_crash() const
     }
 }
 
+class FakeBuffer : public QBuffer
+{
+protected:
+    qint64 writeData(const char *c, qint64 i)
+    {
+        qint64 ai = qMin(m_capacity, i);
+        m_capacity -= ai;
+        return ai ? QBuffer::writeData(c, ai) : 0;
+    }
+public:
+    void setCapacity(int capacity) { m_capacity = capacity; }
+private:
+    qint64 m_capacity;
+};
+
+void tst_QXmlStream::hasError() const
+{
+    {
+        FakeBuffer fb;
+        QVERIFY(fb.open(QBuffer::ReadWrite));
+        fb.setCapacity(1000);
+        QXmlStreamWriter writer(&fb);
+        writer.writeStartDocument();
+        writer.writeEndDocument();
+        QVERIFY(!writer.hasError());
+        QCOMPARE(fb.data(), QByteArray("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"));
+    }
+
+    {
+        // Failure caused by write(QString)
+        FakeBuffer fb;
+        QVERIFY(fb.open(QBuffer::ReadWrite));
+        fb.setCapacity(strlen("<?xml version=\""));
+        QXmlStreamWriter writer(&fb);
+        writer.writeStartDocument();
+        QVERIFY(writer.hasError());
+        QCOMPARE(fb.data(), QByteArray("<?xml version=\""));
+    }
+
+    {
+        // Failure caused by write(char *)
+        FakeBuffer fb;
+        QVERIFY(fb.open(QBuffer::ReadWrite));
+        fb.setCapacity(strlen("<?xml version=\"1.0"));
+        QXmlStreamWriter writer(&fb);
+        writer.writeStartDocument();
+        QVERIFY(writer.hasError());
+        QCOMPARE(fb.data(), QByteArray("<?xml version=\"1.0"));
+    }
+
+    {
+        // Failure caused by write(QStringRef)
+        FakeBuffer fb;
+        QVERIFY(fb.open(QBuffer::ReadWrite));
+        fb.setCapacity(strlen("<?xml version=\"1.0\" encoding=\"UTF-8\"?><test xmlns:"));
+        QXmlStreamWriter writer(&fb);
+        writer.writeStartDocument();
+        writer.writeStartElement("test");
+        writer.writeNamespace("http://foo.bar", "foo");
+        QVERIFY(writer.hasError());
+        QCOMPARE(fb.data(), QByteArray("<?xml version=\"1.0\" encoding=\"UTF-8\"?><test xmlns:"));
+    }
+
+    {
+        // Refusal to write after 1st failure
+        FakeBuffer fb;
+        QVERIFY(fb.open(QBuffer::ReadWrite));
+        fb.setCapacity(10);
+        QXmlStreamWriter writer(&fb);
+        writer.writeStartDocument();
+        QVERIFY(writer.hasError());
+        QCOMPARE(fb.data(), QByteArray("<?xml vers"));
+        fb.setCapacity(1000);
+        writer.writeStartElement("test"); // literal & qstring
+        writer.writeNamespace("http://foo.bar", "foo"); // literal & qstringref
+        QVERIFY(writer.hasError());
+        QCOMPARE(fb.data(), QByteArray("<?xml vers"));
+    }
+
+}
+
 #include "tst_qxmlstream.moc"
 // vim: et:ts=4:sw=4:sts=4