Refactor openMode/keepWriteChannelOpen/closeWriteChannel

Change-Id: I4090533875ce1da864b6f8554ce59dbc1392a142
Reviewed-by: hjk <hjk@qt.io>

src/libs/utils/processutils.cpp

@@ -0,0 +1,58 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "processutils.h"
+#include <QProcess>
+
+namespace Utils {
+
+QIODevice::OpenMode ProcessStartHandler::openMode() const
+{
+    if (m_processMode == ProcessMode::Writer)
+        return QIODevice::ReadWrite; // some writers also read data
+    if (m_writeData.isEmpty())
+        return QIODevice::ReadOnly; // only reading
+    return QIODevice::ReadWrite; // initial write and then reading (close the write channel)
+}
+
+void ProcessStartHandler::handleProcessStart(QProcess *process)
+{
+    if (m_processMode == ProcessMode::Writer)
+        return;
+    if (m_writeData.isEmpty())
+        process->closeWriteChannel();
+}
+
+void ProcessStartHandler::handleProcessStarted(QProcess *process)
+{
+    if (!m_writeData.isEmpty()) {
+        process->write(m_writeData);
+        m_writeData = {};
+        if (m_processMode == ProcessMode::Reader)
+            process->closeWriteChannel();
+    }
+}
+
+} // namespace Utils