QLocalSocket/Win: allow delayed close to work

This mechanism was neither properly designed nor correctly tested
initially on Windows.

[ChangeLog][QtNetwork][Important Behavior Changes] QLocalSocket on
Windows now implements delayed closing, which is consistent with
the behavior on Unix.

Change-Id: Ic3bc427e68eea7f18201f6129df19fbc87d68101
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>

src/network/socket/qlocalsocket.cpp

@@ -208,7 +208,14 @@ QT_BEGIN_NAMESPACE
 
 /*!
     \fn void QLocalSocket::close()
-    \reimp
+
+    Closes the I/O device for the socket and calls disconnectFromServer()
+    to close the socket's connection.
+
+    See QIODevice::close() for a description of the actions that occur when an I/O
+    device is closed.
+
+    \sa abort()
 */
 
 /*!

src/network/socket/qlocalsocket_win.cpp

@@ -377,21 +377,11 @@ bool QLocalSocket::canReadLine() const
 void QLocalSocket::close()
 {
     Q_D(QLocalSocket);
-    if (openMode() == NotOpen)
-        return;
 
     QIODevice::close();
     d->serverName = QString();
     d->fullServerName = QString();
-
-    if (state() != UnconnectedState) {
-        if (bytesToWrite() > 0) {
     disconnectFromServer();
-            return;
-        }
-
-        d->_q_pipeClosed();
-    }
 }
 
 bool QLocalSocket::flush()
@@ -481,10 +471,6 @@ bool QLocalSocket::waitForDisconnected(int msecs)
         qWarning("QLocalSocket::waitForDisconnected() is not allowed in UnconnectedState");
         return false;
     }
-    if (!openMode().testFlag(QIODevice::ReadOnly)) {
-        qWarning("QLocalSocket::waitForDisconnected isn't supported for write only pipes.");
-        return false;
-    }
 
     QDeadlineTimer deadline(msecs);
     while (!d->pipeReader->isPipeClosed()) {

tests/auto/network/socket/qlocalsocket/tst_qlocalsocket.cpp

@@ -1498,17 +1498,16 @@ void tst_QLocalSocket::writeToClientAndDisconnect()
     QVERIFY(server.waitForNewConnection(200));
     QLocalSocket* clientSocket = server.nextPendingConnection();
     QVERIFY(clientSocket);
+    server.close();
 
     char buffer[100];
     memset(buffer, 0, sizeof(buffer));
     for (int i = 0; i < chunks; ++i)
         QCOMPARE(clientSocket->write(buffer, sizeof(buffer)), qint64(sizeof(buffer)));
-    while (clientSocket->bytesToWrite())
-        QVERIFY(clientSocket->waitForBytesWritten());
     clientSocket->close();
-    server.close();
+    QVERIFY(clientSocket->waitForDisconnected());
 
-    client.waitForDisconnected();
+    QVERIFY(client.waitForDisconnected());
     QCOMPARE(readChannelFinishedSpy.count(), 1);
     const QByteArray received = client.readAll();
     QCOMPARE(received.size(), qint64(sizeof(buffer) * chunks));