QtNetwork: Handle FD_CLOSE on Windows

We need to handle FD_CLOSE separately on Windows as this will be sent
only once. When we get FD_CLOSE we need to check if there is more data
available for reading. It there is this might indicate that there is
another FD_READ that we need to handle after the FD_CLOSE. So in this
case we will manually create another close event.

Task-number: QTBUG-19409
Task-number: QTBUG-25386
Change-Id: Ie19906bc3f64fb6a85a508a5ab12caac5d70ccdb
Reviewed-by: Shane Kearns <shane.kearns@accenture.com>

6 files changed, 52 insertions, 0 deletions

diff --git a/src/network/socket/qabstractsocket.cpp b/src/network/socket/qabstractsocket.cpp
index 6b4e48fe62..7c91022759 100644
--- a/src/network/socket/qabstractsocket.cpp
+++ b/src/network/socket/qabstractsocket.cpp
@@ -746,6 +746,44 @@ bool QAbstractSocketPrivate::canReadNotification()
 
 /*! \internal
 
+    Slot connected to the close socket notifier. It's called when the
+    socket is closed.
+*/
+void QAbstractSocketPrivate::canCloseNotification()
+{
+    Q_Q(QAbstractSocket);
+
+#if defined (QABSTRACTSOCKET_DEBUG)
+    qDebug("QAbstractSocketPrivate::canCloseNotification()");
+#endif
+
+    qint64 newBytes = 0;
+    if (isBuffered) {
+        // Try to read to the buffer, if the read fail we can close the socket.
+        newBytes = buffer.size();
+        if (!readFromSocket()) {
+            q->disconnectFromHost();
+            return;
+        }
+        newBytes = buffer.size() - newBytes;
+        if (newBytes) {
+            // If there was still some data to be read from the socket
+            // then we could get another FD_READ. The disconnect will
+            // then occur when we read from the socket again and fail
+            // in canReadNotification or by the manually created
+            // closeNotification below.
+            emit q->readyRead();
+
+            QMetaObject::invokeMethod(socketEngine, "closeNotification", Qt::QueuedConnection);
+        }
+    } else if (socketType == QAbstractSocket::TcpSocket && socketEngine) {
+        emit q->readyRead();
+    }
+}
+
+
+/*! \internal
+
     Slot connected to the write socket notifier. It's called during a
     delayed connect or when the socket is ready for writing.
 */
diff --git a/src/network/socket/qabstractsocket_p.h b/src/network/socket/qabstractsocket_p.h
index 21d85f74fe..b19801882e 100644
--- a/src/network/socket/qabstractsocket_p.h
+++ b/src/network/socket/qabstractsocket_p.h
@@ -77,6 +77,7 @@ public:
     inline void readNotification() { canReadNotification(); }
     inline void writeNotification() { canWriteNotification(); }
     inline void exceptionNotification() {}
+    inline void closeNotification() { canCloseNotification(); }
     void connectionNotification();
 #ifndef QT_NO_NETWORKPROXY
     inline void proxyAuthenticationRequired(const QNetworkProxy &proxy, QAuthenticator *authenticator) {
@@ -87,6 +88,7 @@ public:
 
     bool canReadNotification();
     bool canWriteNotification();
+    void canCloseNotification();
 
     // slots
     void _q_connectToNextAddress();
diff --git a/src/network/socket/qabstractsocketengine.cpp b/src/network/socket/qabstractsocketengine.cpp
index e9e49d41ec..f05fa98a96 100644
--- a/src/network/socket/qabstractsocketengine.cpp
+++ b/src/network/socket/qabstractsocketengine.cpp
@@ -168,6 +168,12 @@ void QAbstractSocketEngine::exceptionNotification()
         receiver->exceptionNotification();
 }
 
+void QAbstractSocketEngine::closeNotification()
+{
+    if (QAbstractSocketEngineReceiver *receiver = d_func()->receiver)
+        receiver->closeNotification();
+}
+
 void QAbstractSocketEngine::connectionNotification()
 {
     if (QAbstractSocketEngineReceiver *receiver = d_func()->receiver)
diff --git a/src/network/socket/qabstractsocketengine_p.h b/src/network/socket/qabstractsocketengine_p.h
index 92d795408f..5264bc4479 100644
--- a/src/network/socket/qabstractsocketengine_p.h
+++ b/src/network/socket/qabstractsocketengine_p.h
@@ -71,6 +71,7 @@ public:
     virtual ~QAbstractSocketEngineReceiver(){}
     virtual void readNotification()= 0;
     virtual void writeNotification()= 0;
+    virtual void closeNotification()= 0;
     virtual void exceptionNotification()= 0;
     virtual void connectionNotification()= 0;
 #ifndef QT_NO_NETWORKPROXY
@@ -173,6 +174,7 @@ public:
 public Q_SLOTS:
     void readNotification();
     void writeNotification();
+    void closeNotification();
     void exceptionNotification();
     void connectionNotification();
 #ifndef QT_NO_NETWORKPROXY
diff --git a/src/network/socket/qnativesocketengine.cpp b/src/network/socket/qnativesocketengine.cpp
index f2e2f692ac..3dca7aa9ee 100644
--- a/src/network/socket/qnativesocketengine.cpp
+++ b/src/network/socket/qnativesocketengine.cpp
@@ -1142,6 +1142,9 @@ bool QReadNotifier::event(QEvent *e)
     if (e->type() == QEvent::SockAct) {
         engine->readNotification();
         return true;
+    } else if (e->type() == QEvent::SockClose) {
+        engine->closeNotification();
+        return true;
     }
     return QSocketNotifier::event(e);
 }
diff --git a/src/network/socket/qtcpserver.cpp b/src/network/socket/qtcpserver.cpp
index 4d8aad0dba..7955928727 100644
--- a/src/network/socket/qtcpserver.cpp
+++ b/src/network/socket/qtcpserver.cpp
@@ -134,6 +134,7 @@ public:
 
     // from QAbstractSocketEngineReceiver
     void readNotification();
+    void closeNotification() { readNotification(); }
     inline void writeNotification() {}
     inline void exceptionNotification() {}
     inline void connectionNotification() {}