src/corelib/io/qwindowspipewriter.cpp
changeset 0 1918ee327afb
child 4 3b1da2848fc7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/corelib/io/qwindowspipewriter.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,171 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwindowspipewriter_p.h"
+
+QT_BEGIN_NAMESPACE
+
+#ifndef QT_NO_THREAD
+
+QWindowsPipeWriter::QWindowsPipeWriter(HANDLE pipe, QObject * parent)
+    : QThread(parent),
+      writePipe(INVALID_HANDLE_VALUE),
+      quitNow(false),
+      hasWritten(false)
+{
+#if !defined(Q_OS_WINCE) || (_WIN32_WCE >= 0x600)
+    DuplicateHandle(GetCurrentProcess(), pipe, GetCurrentProcess(),
+                         &writePipe, 0, FALSE, DUPLICATE_SAME_ACCESS);
+#else
+    Q_UNUSED(pipe);
+    writePipe = GetCurrentProcess();
+#endif
+}
+
+QWindowsPipeWriter::~QWindowsPipeWriter()
+{
+    lock.lock();
+    quitNow = true;
+    waitCondition.wakeOne();
+    lock.unlock();
+    if (!wait(100))
+        terminate();
+#if !defined(Q_OS_WINCE) || (_WIN32_WCE >= 0x600)
+    CloseHandle(writePipe);
+#endif
+}
+
+bool QWindowsPipeWriter::waitForWrite(int msecs)
+{
+    QMutexLocker locker(&lock);
+    bool hadWritten = hasWritten;
+    hasWritten = false;
+    if (hadWritten)
+        return true;
+    if (!waitCondition.wait(&lock, msecs))
+        return false;
+    hadWritten = hasWritten;
+    hasWritten = false;
+    return hadWritten;
+}
+
+qint64 QWindowsPipeWriter::write(const char *ptr, qint64 maxlen)
+{
+    if (!isRunning())
+        return -1;
+
+    QMutexLocker locker(&lock);
+    data.append(QByteArray(ptr, maxlen));
+    waitCondition.wakeOne();
+    return maxlen;
+}
+
+void QWindowsPipeWriter::run()
+{
+    OVERLAPPED overl = {0, 0, 0, 0, NULL};
+    overl.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
+    forever {
+        lock.lock();
+        while(data.isEmpty() && (!quitNow)) {
+            waitCondition.wakeOne();
+            waitCondition.wait(&lock);
+        }
+
+        if (quitNow) {
+            lock.unlock();
+            quitNow = false;
+	    break;
+        }
+
+        QByteArray copy = data;
+
+        lock.unlock();
+
+        const char *ptrData = copy.data();
+        qint64 maxlen = copy.size();
+        qint64 totalWritten = 0;
+        overl.Offset = 0;
+        overl.OffsetHigh = 0;
+        while ((!quitNow) && totalWritten < maxlen) {
+            DWORD written = 0;
+            // Write 2k at a time to prevent flooding the pipe. If you
+            // write too much (4k-8k), the pipe can close
+            // unexpectedly.
+            if (!WriteFile(writePipe, ptrData + totalWritten,
+                    qMin<int>(2048, maxlen - totalWritten), &written, &overl)) {
+                if (GetLastError() == 0xE8/*NT_STATUS_INVALID_USER_BUFFER*/) {
+                    // give the os a rest
+                    msleep(100);
+                    continue;
+                }
+#ifndef Q_OS_WINCE
+                if (GetLastError() == ERROR_IO_PENDING) {
+                  if (!GetOverlappedResult(writePipe, &overl, &written, TRUE)) {
+                      CloseHandle(overl.hEvent);
+                      return;
+                  }
+                } else {
+                    CloseHandle(overl.hEvent);
+                    return;
+                }
+#else
+                return;
+#endif
+            }
+            totalWritten += written;
+#if defined QPIPEWRITER_DEBUG
+            qDebug("QWindowsPipeWriter::run() wrote %d %d/%d bytes",
+			    written, int(totalWritten), int(maxlen));
+#endif
+            lock.lock();
+            data.remove(0, written);
+            hasWritten = true;
+            lock.unlock();
+        }
+        emit bytesWritten(totalWritten);
+        emit canWrite();
+    }
+    CloseHandle(overl.hEvent);
+}
+
+#endif //QT_NO_THREAD
+
+QT_END_NAMESPACE