2 files changed, 58 insertions, 23 deletions

diff --git a/src/corelib/xml/qxmlstream.cpp b/src/corelib/xml/qxmlstream.cpp
index f6ae3571ab..c1ed410de7 100644
--- a/src/corelib/xml/qxmlstream.cpp
+++ b/src/corelib/xml/qxmlstream.cpp
@@ -2980,7 +2980,8 @@ public:
     uint inEmptyElement :1;
     uint lastWasStartElement :1;
     uint wroteSomething :1;
-    uint hasError :1;
+    uint hasIoError :1;
+    uint hasEncodingError :1;
     uint autoFormatting :1;
     uint isCodecASCIICompatible :1;
     QByteArray autoFormattingIndent;
@@ -3016,7 +3017,8 @@ QXmlStreamWriterPrivate::QXmlStreamWriterPrivate(QXmlStreamWriter *q)
     checkIfASCIICompatibleCodec();
     inStartElement = inEmptyElement = false;
     wroteSomething = false;
-    hasError = false;
+    hasIoError = false;
+    hasEncodingError = false;
     lastWasStartElement = false;
     lastNamespaceDeclaration = 1;
     autoFormatting = false;
@@ -3043,15 +3045,19 @@ void QXmlStreamWriterPrivate::checkIfASCIICompatibleCodec()
 void QXmlStreamWriterPrivate::write(const QStringRef &s)
 {
     if (device) {
-        if (hasError)
+        if (hasIoError)
             return;
 #ifdef QT_NO_TEXTCODEC
         QByteArray bytes = s.toLatin1();
 #else
         QByteArray bytes = encoder->fromUnicode(s.constData(), s.size());
+        if (encoder->hasFailure()) {
+            hasEncodingError = true;
+            return;
+        }
 #endif
         if (device->write(bytes) != bytes.size())
-            hasError = true;
+            hasIoError = true;
     }
     else if (stringDevice)
         s.appendTo(stringDevice);
@@ -3062,15 +3068,19 @@ void QXmlStreamWriterPrivate::write(const QStringRef &s)
 void QXmlStreamWriterPrivate::write(const QString &s)
 {
     if (device) {
-        if (hasError)
+        if (hasIoError)
             return;
 #ifdef QT_NO_TEXTCODEC
         QByteArray bytes = s.toLatin1();
 #else
         QByteArray bytes = encoder->fromUnicode(s);
+        if (encoder->hasFailure()) {
+            hasEncodingError = true;
+            return;
+        }
 #endif
         if (device->write(bytes) != bytes.size())
-            hasError = true;
+            hasIoError = true;
     }
     else if (stringDevice)
         stringDevice->append(s);
@@ -3084,25 +3094,47 @@ void QXmlStreamWriterPrivate::writeEscaped(const QString &s, bool escapeWhitespa
     escaped.reserve(s.size());
     for ( int i = 0; i < s.size(); ++i ) {
         QChar c = s.at(i);
-        if (c.unicode() == '<' )
+        switch (c.unicode()) {
+        case '<':
             escaped.append(QLatin1String("&lt;"));
-        else if (c.unicode() == '>' )
+            break;
+        case '>':
             escaped.append(QLatin1String("&gt;"));
-        else if (c.unicode() == '&' )
+            break;
+        case '&':
             escaped.append(QLatin1String("&amp;"));
-        else if (c.unicode() == '\"' )
+            break;
+        case '\"':
             escaped.append(QLatin1String("&quot;"));
-        else if (escapeWhitespace && c.isSpace()) {
-            if (c.unicode() == '\n')
+            break;
+        case '\t':
+            if (escapeWhitespace)
+                escaped.append(QLatin1String("&#9;"));
+            else
+                escaped += c;
+            break;
+        case '\n':
+            if (escapeWhitespace)
                 escaped.append(QLatin1String("&#10;"));
-            else if (c.unicode() == '\r')
+            else
+                escaped += c;
+            break;
+        case '\v':
+        case '\f':
+            hasEncodingError = true;
+            break;
+        case '\r':
+            if (escapeWhitespace)
                 escaped.append(QLatin1String("&#13;"));
-            else if (c.unicode() == '\t')
-                escaped.append(QLatin1String("&#9;"));
             else
                 escaped += c;
-        } else {
-            escaped += QChar(c);
+            break;
+        default:
+            if (c.unicode() > 0x1f && c.unicode() < 0xfffe)
+                escaped += c;
+            else
+                hasEncodingError = true;
+            break;
         }
     }
     write(escaped);
@@ -3112,11 +3144,11 @@ void QXmlStreamWriterPrivate::writeEscaped(const QString &s, bool escapeWhitespa
 void QXmlStreamWriterPrivate::write(const char *s, int len)
 {
     if (device) {
-        if (hasError)
+        if (hasIoError)
             return;
         if (isCodecASCIICompatible) {
             if (device->write(s, len) != len)
-                hasError = true;
+                hasIoError = true;
             return;
         }
     }
@@ -3400,15 +3432,18 @@ int QXmlStreamWriter::autoFormattingIndent() const
 }
 
 /*!
-    Returns \c true if the stream failed to write to the underlying device.
+    Returns \c true if writing failed.
+
+    This can happen if the stream failed to write to the underlying
+    device or if the data to be written contained invalid characters.
 
     The error status is never reset. Writes happening after the error
-    occurred are ignored, even if the error condition is cleared.
+    occurred may be ignored, even if the error condition is cleared.
  */
 bool QXmlStreamWriter::hasError() const
 {
     Q_D(const QXmlStreamWriter);
-    return d->hasError;
+    return d->hasIoError || d->hasEncodingError;
 }
 
 /*!
diff --git a/src/corelib/xml/qxmlstream.h b/src/corelib/xml/qxmlstream.h
index bf6ddefcdd..2350d12dd6 100644
--- a/src/corelib/xml/qxmlstream.h
+++ b/src/corelib/xml/qxmlstream.h
@@ -120,7 +120,7 @@ public:
           reserved(other.reserved),
           m_isDefault(other.m_isDefault)
     {
-        other.reserved = Q_NULLPTR;
+        other.reserved = nullptr;
     }
     QXmlStreamAttribute &operator=(QXmlStreamAttribute &&other) Q_DECL_NOTHROW // = default;
     {